owner?  If the two companies are both filing taxes as either a sole proprietor (schedule c) or a partnership (form 1065)

then you can use an equity transfer

company S payments to company T would be an owner equity draw in company S
and an owner equity investment in company T and the […]

Resolution for 'company S payments issue: 'How Do I fix inter-mingling of monies?' available: Yes.

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

For more information about resolving issues related to company S payments in Quickbooks/QBO or to get support for the issue 'How Do I fix inter-mingling of monies?', click the link below: