Why were EFile attachments to state tax return not received by state?

[TAD]

Maryland tax notice denying credit for other state taxes paid.  Maryland did not receive required support that WAS attached (EFile PDF attachment) to E-Filed return

[sjrcpa]

 Send it to them again. MD and VA are notorious for saying they didn't get it.

[Accountant-Man]

PA and NJ are also states that enjoy messing with you and saying that they didn't get the attachments. We don't know if that is true, but that does allow them to keep your money for a longer period.