You can’t create subvendors.
ATT stands for one of the phone companies.
Resolution for 'ATT accounts issue: 'What are ATT accounts?' available: Yes.
The ATT accounts 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 ATT accounts issue yourself by looking for a resolution described in the article. If it is a complex ATT accounts issue or you are unable to solve the issue, you may contact us by clicking here or by using other ATT accounts support options.
For more information about resolving issues related to ATT accounts in Quickbooks/QBO or to get support for the issue 'What are ATT accounts?', click the link below: