I had the same problem with a Canon 560 also using DL size envelopes. If I remember correctly the way I fixed it was that, by accident, I changed the envelope size to Monarch (I think) and everything worked.
I love these technical solutions!!
Dell XPS 13 9370 (2018) review
No need to scan sketches into your computer with Moleskine's new smart pen
Streaming : Netflix ou Amazon Prime Video ?