When looking at Tax Return reports, Sales and Sellers use Tax Jurisdiction detail and choosing Sellers Use Tax as a filter, there are no transactions but there are when choosing Sales Tax.
If nexus is set to Sales Tax for a state instead of Sales or Sellers Use, tax is calculated specifically as sales tax, not sellers use and is reported as such for filing purposes.
Nexus needs to be reset (IF APPROPRIATE FOR YOU) to sales or sellers use. You registered specifically for one type or the other with the state in question. Learn how to add or edit nexus jurisdictions.
Once changed, if filing has not occurred yet, you will have to edit each transaction in the Admin Console and after changing the setting, re-save them as committed to change the tax type reported to Avalara. Then, the LWS will have to be rebuilt to move the values internally.
For more information, read Admin Console reports.