I am assuming you have created a retainer account in your chart of accounts. If you haven’t done so already,

Go to the gear icon then Chart of Accounts
Click New
On the dropdown for Category Type Other current liability and Trust Accounts – Liabilities for the Detail type.

Create a Product Service item using Trust or Retainer […]

Resolution for 'Accounts Liabilities issue: 'invoice from retainer account' available: Yes.

The Accounts Liabilities 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 Accounts Liabilities issue yourself by looking for a resolution described in the article. If it is a complex Accounts Liabilities issue or you are unable to solve the issue, you may contact us by clicking here or by using other Accounts Liabilities support options.

For more information about resolving issues related to Accounts Liabilities in Quickbooks/QBO or to get support for the issue 'invoice from retainer account', click the link below: