Please find the steps to resolve the issue of associating
account in WHMCS.
1. Check the following for the active product instance in WHMCS admin portal and update them accordingly.
any existing entry for the subscription ID in the [AzurePackSubscriptionsInfo]
Sample Query: delete from [DBName].[API].[AzurePackSubscriptionsInfo]
where Id = <Id to delete>
3. Click the Associate Account button. This should create a new entry in the [AzurePackSubscriptionsInfo] table with the appropriate SubscriptionId and ProductInstanceId (ProductInstanceId will be present in the AddtionalInfoJson column)