Because they represent territories and associated jurisdictions, not states, they do not possess the same parliamentary rights afforded Members. In the House

The delegates and the resident commissioner may not vote in or preside over the House. In Committee of the Whole House on the State of the Union

Under the rules of the 115 th Congress (2017-2018), the delegates and the resident commissioner may not vote in the Committee of the Whole House on the State of the Union.
As officers who represent territories and properties possessed or administered by the United States but not admitted to statehood, the five House delegates and the resident commissioner from Puerto Rico do not enjoy all the same parliamentary rights as Members of the House. They may vote and otherwise act similarly to Members in legislative committee. They may not vote on the House floor but may participate in debate and make most motions there. Under the rules of the 115th Congress (2017-2018), the delegates and resident commissioner may not vote in, but are permitted to preside over, the Committee of the Whole.
This report will be updated as circumstances warrant.