diff --git a/migration/1773434400000-AddArkBtcToBaseFees.js b/migration/1773434400000-AddArkBtcToBaseFees.js
new file mode 100644
index 0000000000..9ea1109e7e
--- /dev/null
+++ b/migration/1773434400000-AddArkBtcToBaseFees.js
@@ -0,0 +1,21 @@
+module.exports = class AddArkBtcToBaseFees1773434400000 {
+  name = 'AddArkBtcToBaseFees1773434400000';
+
+  async up(queryRunner) {
+    // Add Ark/BTC (asset 426) to all Tier2 base fees that use explicit asset lists
+    await queryRunner.query(`
+      UPDATE "dbo"."fee"
+      SET "assets" = "assets" + ';426'
+      WHERE "id" IN (4, 5, 6, 10, 11, 12, 16, 17, 18)
+        AND ';' + "assets" + ';' NOT LIKE '%;426;%'
+    `);
+  }
+
+  async down(queryRunner) {
+    await queryRunner.query(`
+      UPDATE "dbo"."fee"
+      SET "assets" = REPLACE("assets", ';426', '')
+      WHERE "id" IN (4, 5, 6, 10, 11, 12, 16, 17, 18)
+    `);
+  }
+};
diff --git a/src/subdomains/generic/user/models/auth/auth.service.ts b/src/subdomains/generic/user/models/auth/auth.service.ts
index d9fc96467d..9ea6e69cf6 100644
--- a/src/subdomains/generic/user/models/auth/auth.service.ts
+++ b/src/subdomains/generic/user/models/auth/auth.service.ts
@@ -188,7 +188,7 @@ export class AuthService {
         type: RecommendationType.INVITATION,
         method: RecommendationMethod.MAIL,
       });
-      await this.recommendationService.setRecommenderRefCode(recommendation);
+      if (recommendation) await this.recommendationService.setRecommenderRefCode(recommendation);
     }
 
     await this.checkIpBlacklistFor(user.userData, userIp);