diff --git a/packages/backend/src/server/api/SigninApiService.ts b/packages/backend/src/server/api/SigninApiService.ts
index 687913731..cd5623aa9 100644
--- a/packages/backend/src/server/api/SigninApiService.ts
+++ b/packages/backend/src/server/api/SigninApiService.ts
@@ -4,9 +4,8 @@
  */
 
 import { Inject, Injectable } from '@nestjs/common';
-//import bcrypt from 'bcryptjs';
+import bcrypt from 'bcryptjs';
 import * as argon2 from 'argon2';
-import bcrypt from "bcryptjs";
 import * as OTPAuth from 'otpauth';
 import { IsNull } from 'typeorm';
 import { DI } from '@/di-symbols.js';
@@ -26,22 +25,7 @@ import { RateLimiterService } from './RateLimiterService.js';
 import { SigninService } from './SigninService.js';
 import type { AuthenticationResponseJSON } from '@simplewebauthn/typescript-types';
 import type { FastifyReply, FastifyRequest } from 'fastify';
-async function hashPassword(password: string): Promise<string> {
-	return argon2.hash(password);
-}
-async function comparePassword(
-	password: string,
-	hash: string,
-): Promise<boolean> {
-	if (isOldAlgorithm(hash)) return bcrypt.compare(password, hash);
 
-	return argon2.verify(hash, password);
-}
-
-function isOldAlgorithm(hash: string): boolean {
-	// bcrypt hashes start with $2[ab]$
-	return hash.startsWith("$2");
-}
 @Injectable()
 export class SigninApiService {
 	constructor(
@@ -140,11 +124,8 @@ export class SigninApiService {
 		const profile = await this.userProfilesRepository.findOneByOrFail({ userId: user.id });
 
 		// Compare password
-		const same = await comparePassword(password, profile.password!);
-		if (same && isOldAlgorithm(profile.password!)) {
-			profile.password = await hashPassword(password);
-			await this.userProfilesRepository.save(profile);
-		}
+		const same = await argon2.verify(profile.password!, password) || bcrypt.compareSync(password, profile.password!);
+
 		const fail = async (status?: number, failure?: { id: string }) => {
 			// Append signin history
 			await this.signinsRepository.insert({
@@ -161,6 +142,12 @@ export class SigninApiService {
 
 		if (!profile.twoFactorEnabled) {
 			if (same) {
+				if (profile.password!.startsWith('$2')) {
+					const newHash = await argon2.hash(password);
+					this.userProfilesRepository.update(user.id, {
+						password: newHash
+					});
+				}
 				return this.signinService.signin(request, reply, user);
 			} else {
 				return await fail(403, {
@@ -177,6 +164,12 @@ export class SigninApiService {
 			}
 
 			try {
+				if (profile.password!.startsWith('$2')) {
+					const newHash = await argon2.hash(password);
+					this.userProfilesRepository.update(user.id, {
+						password: newHash
+					});
+				}
 				await this.userAuthService.twoFactorAuthenticate(profile, token);
 			} catch (e) {
 				return await fail(403, {