diff --git a/src/components/call/index.ts b/src/components/call/index.ts
index 57d47804..f2e4fc0d 100644
--- a/src/components/call/index.ts
+++ b/src/components/call/index.ts
@@ -10,6 +10,7 @@ import { attachClickEvent } from "../../helpers/dom/clickEvent";
 import ControlsHover from "../../helpers/dom/controlsHover";
 import findUpClassName from "../../helpers/dom/findUpClassName";
 import { addFullScreenListener, cancelFullScreen, isFullScreen, requestFullScreen } from "../../helpers/dom/fullScreen";
+import replaceContent from "../../helpers/dom/replaceContent";
 import MovablePanel from "../../helpers/movablePanel";
 import onMediaLoad from "../../helpers/onMediaLoad";
 import themeController from "../../helpers/themeController";
@@ -441,7 +442,7 @@ export default class PopupCall extends PopupElement {
 
     if(!this.emojisSubtitle.textContent && connectionState < CALL_STATE.EXCHANGING_KEYS) {
       Promise.resolve(instance.getEmojisFingerprint()).then((emojis) => {
-        this.emojisSubtitle.append(wrapEmojiText(emojis.join('')));
+        replaceContent(this.emojisSubtitle, wrapEmojiText(emojis.join('')));
       });
     }
 
diff --git a/src/helpers/bigInt/bigIntConstants.ts b/src/helpers/bigInt/bigIntConstants.ts
new file mode 100644
index 00000000..d2ae8f26
--- /dev/null
+++ b/src/helpers/bigInt/bigIntConstants.ts
@@ -0,0 +1,5 @@
+import bigInt from 'big-integer';
+
+export const safeBigInt = bigInt(Number.MAX_SAFE_INTEGER);
+export const ulongBigInt = bigInt(bigInt[2]).pow(64);
+export const longBigInt = ulongBigInt.divide(bigInt[2]);
diff --git a/src/helpers/bigInt/bigIntConversion.ts b/src/helpers/bigInt/bigIntConversion.ts
index 088e7359..65c9876c 100644
--- a/src/helpers/bigInt/bigIntConversion.ts
+++ b/src/helpers/bigInt/bigIntConversion.ts
@@ -1,4 +1,5 @@
 import bigInt from 'big-integer';
+import { longBigInt, ulongBigInt } from './bigIntConstants';
 
 export function bigIntFromBytes(bytes: Uint8Array | number[], base = 256) {
   return bigInt.fromArray(bytes instanceof Uint8Array ? [...bytes] : bytes, base);
@@ -7,3 +8,11 @@ export function bigIntFromBytes(bytes: Uint8Array | number[], base = 256) {
 export function bigIntToBytes(bigInt: bigInt.BigInteger) {
   return new Uint8Array(bigInt.toArray(256).value);
 }
+
+export function bigIntToSigned(bigInt: bigInt.BigInteger) {
+  return bigInt.greater(longBigInt) ? bigInt.minus(ulongBigInt) : bigInt;
+}
+
+export function bigIntToUnsigned(bigInt: bigInt.BigInteger) {
+  return bigInt.isNegative() ? ulongBigInt.add(bigInt) : bigInt;
+}
diff --git a/src/lib/calls/callsController.ts b/src/lib/calls/callsController.ts
index 4b71b235..62948a1f 100644
--- a/src/lib/calls/callsController.ts
+++ b/src/lib/calls/callsController.ts
@@ -115,7 +115,8 @@ export class CallsController extends EventListenerBase<{
 
           const {key, key_fingerprint} = await this.managers.appCallsManager.computeKey(g_a, dh.b, dh.p);
           if(call.key_fingerprint !== key_fingerprint) {
-            this.log.error('Incorrect key fingerprint', call.key_fingerprint, key_fingerprint);
+            this.log.error('Incorrect key fingerprint', call.key_fingerprint, key_fingerprint, g_a, dh);
+            instance.hangUp('phoneCallDiscardReasonDisconnect');
             break;
           }
 
diff --git a/src/lib/crypto/computeDhKey.ts b/src/lib/crypto/computeDhKey.ts
index 7b1b9762..230d673e 100644
--- a/src/lib/crypto/computeDhKey.ts
+++ b/src/lib/crypto/computeDhKey.ts
@@ -4,14 +4,14 @@
  * https://github.com/morethanwords/tweb/blob/master/LICENSE
  */
 
-import { bigIntFromBytes } from "../../helpers/bigInt/bigIntConversion";
+import { bigIntFromBytes, bigIntToSigned } from "../../helpers/bigInt/bigIntConversion";
 import cryptoWorker from "./cryptoMessagePort";
 
 export default async function computeDhKey(g_b: Uint8Array, a: Uint8Array, p: Uint8Array) {
   const key = await cryptoWorker.invokeCrypto('mod-pow', g_b, a, p);
   const keySha1Hashed = await cryptoWorker.invokeCrypto('sha1', key);
-  const key_fingerprint = keySha1Hashed.slice(-8).reverse(); // key_fingerprint: key_fingerprint as any // ! it doesn't work
-  const key_fingerprint_long = bigIntFromBytes(key_fingerprint).toString(10); // bigInt2str(str2bigInt(bytesToHex(key_fingerprint), 16), 10);
+  const key_fingerprint = keySha1Hashed.slice(-8).reverse();
+  const key_fingerprint_long = bigIntToSigned(bigIntFromBytes(key_fingerprint)).toString(10);
 
   return {key, key_fingerprint: key_fingerprint_long};
 }
diff --git a/src/lib/mtproto/tl_utils.ts b/src/lib/mtproto/tl_utils.ts
index 2c8de448..ab9955bb 100644
--- a/src/lib/mtproto/tl_utils.ts
+++ b/src/lib/mtproto/tl_utils.ts
@@ -17,16 +17,14 @@ import isObject from '../../helpers/object/isObject';
 import gzipUncompress from '../../helpers/gzipUncompress';
 import bigInt from 'big-integer';
 import ulongFromInts from '../../helpers/long/ulongFromInts';
+import { safeBigInt } from '../../helpers/bigInt/bigIntConstants';
+import { bigIntToSigned, bigIntToUnsigned } from '../../helpers/bigInt/bigIntConversion';
 
 const boolFalse = +Schema.API.constructors.find((c) => c.predicate === 'boolFalse').id;
 const boolTrue = +Schema.API.constructors.find((c) => c.predicate === 'boolTrue').id;
 const vector = +Schema.API.constructors.find((c) => c.predicate === 'vector').id;
 const gzipPacked = +Schema.MTProto.constructors.find((c) => c.predicate === 'gzip_packed').id;
 
-const safeBigInt = bigInt(Number.MAX_SAFE_INTEGER);
-const ulongBigInt = bigInt(bigInt[2]).pow(64);
-const longBigInt = ulongBigInt.divide(bigInt[2]);
-
 class TLSerialization {
   private maxLength = 2048; // 2Kb
   private offset = 0; // in bytes
@@ -151,11 +149,7 @@ class TLSerialization {
       }
     }
 
-    let _bigInt = bigInt(sLong as string);
-    if(_bigInt.isNegative()) { // make it unsigned
-      _bigInt = ulongBigInt.add(_bigInt);
-    }
-
+    const _bigInt = bigIntToUnsigned(bigInt(sLong as string));
     const {quotient, remainder} = _bigInt.divmod(0x100000000);
     const high = quotient.toJSNumber();
     const low = remainder.toJSNumber();
@@ -504,8 +498,8 @@ class TLDeserialization<FetchLongAs extends Long> {
     const iHigh = this.readInt((field || '') + ':long[high]');
 
     let ulong = ulongFromInts(iHigh, iLow);
-    if(/* !unsigned &&  */!this.mtproto && ulong.greater(longBigInt)) { // make it signed
-      ulong = ulong.minus(ulongBigInt);
+    if(/* !unsigned &&  */!this.mtproto) { // make it signed
+      ulong = bigIntToSigned(ulong);
     }
 
     if(!this.mtproto) {
diff --git a/src/scss/partials/popups/_call.scss b/src/scss/partials/popups/_call.scss
index ab42559b..1269e9b2 100644
--- a/src/scss/partials/popups/_call.scss
+++ b/src/scss/partials/popups/_call.scss
@@ -10,6 +10,7 @@
   #{$parent} {
     &-header {
       width: 100%;
+      justify-content: space-between;
     }
 
     &-title {