“I also creat bank sub accounts to keep track of different of funds.”

You didn’t need to do this, but I see it in data files moved from Pro to Premier, as well.

“Our church purchased church building with mortgage loan in 2016. When I enter journal entries of fixed assets blanaces for church […]

Resolution for 'bank sub issue: 'Journal entries for beginning account balance and class' available: Yes.

The bank sub issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the bank sub issue yourself by looking for a resolution described in the article. If it is a complex bank sub issue or you are unable to solve the issue, you may contact us by clicking here or by using other bank sub support options.

For more information about resolving issues related to bank sub in Quickbooks/QBO or to get support for the issue 'Journal entries for beginning account balance and class', click the link below: