QB Issue Resolution:

In the US, each business has to have its own accounting file, file its own tax form (sch C for sole proprietors), and stand on its own financially.

So a sole proprietor might have more than one schedule C as part of his 1040 filing.

short answer is a new business should have its own subscription in QBO

And in QBO you can not have multiple business templates, change a template they all change

Resolution for Issue 'QBO user: How do I set up our new DBA that has the same tax id# and same location number as my current company?' available: Yes (Solved).
Source: Intuit Community forum.

QBO user: How do I set up our new DBA that has the same tax id# and same location number as my current company?: this 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 issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.

Support for accounting file
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Error Recovery for accounting file [Canada]
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