If you mean Sales Tax, and there is no link for add/edit sales tax, then you are one of the accounts that intuit is using to test the new automatic sales tax and you can not make any adjustments, please post exactly what the issue is

Resolution for 'adjust them issue: 'I can’t seem to adjust the tax rates. Where do I go to adjust them?' available: Yes.

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

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