Printing envelopes with iPad (Actually, NOT printing envelopes!)

I am running iPadOS 14.3 on an iPad 5th Generation. This problem has been here for the last several opsystem versions. I don’t know when it started.

Regardless of what app I am using, when I try to print a document on a standard envelope size (4.13 X 9.5) the iPad tries to print it on 8.5 X 11 paper, which the printer rejects. I try using HP Smart or the standard AirPrint with the same result. It’s not the printer (an HP) since I had no issue with my (now deceased) Dell desktop, so it’s in the iPad. HELP!