diff --git a/src/config/config.ts b/src/config/config.ts
index 2ea061eb21..618beb9eb8 100644
--- a/src/config/config.ts
+++ b/src/config/config.ts
@@ -47,6 +47,7 @@ export class Configuration {
   kycVersion: Version = '2';
   defaultVersionString = `v${this.defaultVersion}`;
   defaultRef = '000-000';
+  defaultWalletId = 1;
   transactionRefundExpirySeconds = 300; // 5 minutes - enough time to fill out the refund form
   refRewardManualCheckLimit = 3000; // EUR
   txRequestWaitingExpiryDays = 7;
diff --git a/src/subdomains/core/custody/services/custody.service.ts b/src/subdomains/core/custody/services/custody.service.ts
index 7feda31aad..27dfc16a48 100644
--- a/src/subdomains/core/custody/services/custody.service.ts
+++ b/src/subdomains/core/custody/services/custody.service.ts
@@ -54,7 +54,7 @@ export class CustodyService {
     const custodyWallet = EvmUtil.createWallet(Config.blockchain.evm.custodyAccount(addressIndex));
     const signature = await custodyWallet.signMessage(Config.auth.signMessageGeneral + custodyWallet.address);
 
-    const account = await this.userDataService.getUserData(accountId);
+    const account = await this.userDataService.getUserData(accountId, { users: true });
     if (!account) throw new NotFoundException('User not found');
 
     const custodyUser = await this.userService.createUser(
diff --git a/src/subdomains/generic/user/models/user-data/user-data.service.ts b/src/subdomains/generic/user/models/user-data/user-data.service.ts
index 0f2193c108..e4a55f545b 100644
--- a/src/subdomains/generic/user/models/user-data/user-data.service.ts
+++ b/src/subdomains/generic/user/models/user-data/user-data.service.ts
@@ -1166,6 +1166,7 @@ export class UserDataService {
     // optional master updates
     if (master.status === UserDataStatus.KYC_ONLY && slave.users.length && slave.wallet) master.wallet = slave.wallet;
     if ([UserDataStatus.KYC_ONLY, UserDataStatus.DEACTIVATED].includes(master.status)) master.status = slave.status;
+    if ((!master.wallet || master.wallet.id === Config.defaultWalletId) && slave.wallet) master.wallet = slave.wallet;
     if (!master.amlListAddedDate && slave.amlListAddedDate) {
       master.amlListAddedDate = slave.amlListAddedDate;
       master.amlListExpiredDate = slave.amlListExpiredDate;
diff --git a/src/subdomains/generic/user/models/user/user.service.ts b/src/subdomains/generic/user/models/user/user.service.ts
index bb0a5147be..be1beb2a86 100644
--- a/src/subdomains/generic/user/models/user/user.service.ts
+++ b/src/subdomains/generic/user/models/user/user.service.ts
@@ -240,11 +240,14 @@ export class UserService {
       addressType: CryptoService.getAddressType(data.address),
     });
     const userIsActive = data.userData?.status === UserDataStatus.ACTIVE;
+    const lastExistingUsedRef = data.userData?.users
+      ? Util.sort(data.userData.users, 'id', 'DESC').find((u) => u.usedRef !== Config.defaultRef)?.usedRef
+      : undefined;
 
     user.ip = data.ip;
     user.ipCountry = this.geoLocationService.getCountry(data.ip);
     user.wallet = data.wallet ?? (await this.walletService.getDefault());
-    user.usedRef = await this.checkRef(user, data.usedRef);
+    user.usedRef = await this.checkRef(user, data.usedRef, lastExistingUsedRef);
     user.origin = data.origin;
     user.custodyProvider = data.custodyProvider;
     if (userIsActive) user.status = UserStatus.ACTIVE;
@@ -597,14 +600,14 @@ export class UserService {
     await this.userDataRepo.activateUserData(userData);
   }
 
-  private async checkRef(user: User, usedRef: string): Promise<string> {
-    const refUser = await this.getRefUser(usedRef);
-    return usedRef === null ||
-      usedRef === user.ref ||
-      (usedRef && !refUser) ||
-      user?.userData?.id === refUser?.userData?.id
-      ? Config.defaultRef
-      : usedRef;
+  private async checkRef(user: User, usedRef?: string, existingUsedRef?: string): Promise<string> {
+    if (usedRef) {
+      const refUser = await this.getRefUser(usedRef);
+      const isValidRef = usedRef !== user.ref && refUser && user?.userData?.id !== refUser?.userData?.id;
+      if (isValidRef) return usedRef;
+    }
+
+    return existingUsedRef ?? Config.defaultRef;
   }
 
   public async getTotalRefRewards(): Promise<number> {
diff --git a/src/subdomains/generic/user/models/wallet/wallet.service.ts b/src/subdomains/generic/user/models/wallet/wallet.service.ts
index 966e499314..068aa02508 100644
--- a/src/subdomains/generic/user/models/wallet/wallet.service.ts
+++ b/src/subdomains/generic/user/models/wallet/wallet.service.ts
@@ -1,4 +1,5 @@
 import { Injectable, NotFoundException } from '@nestjs/common';
+import { Config } from 'src/config/config';
 import { WalletRepository } from 'src/subdomains/generic/user/models/wallet/wallet.repository';
 import { FindOptionsRelations } from 'typeorm';
 import { WalletDto } from './dto/wallet.dto';
@@ -40,6 +41,6 @@ export class WalletService {
   }
 
   async getDefault(): Promise<Wallet> {
-    return this.repo.findOneCachedBy('default', { id: 1 });
+    return this.repo.findOneCachedBy('default', { id: Config.defaultWalletId });
   }
 }