QB Issue Resolution:

I’m glad that you took the time to post in the Community.

You’ll want to enter the official tax ID number that is assigned to your company in the Business ID No. field. You may to ask your accountant or tax agency if it’s the Tax Registration Number (TRN) or not. This way, we can be sure that your tax information will be correct.

You can check out the article about setting sales VAT rates for additional reference.

Resolution for Issue 'UAE VAT is the Business ID No. the registered business number or the Tax Registration Number?' available: Yes (Solved).
Source: Intuit Community forum.

UAE VAT is the Business ID No. the registered business number or the Tax Registration Number?: 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 Business ID No
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Error Recovery for Business ID No [Canada]
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