This year, my husband and I used his account to file married jointly, unlike previous years where we used our own accounts. What do I need to do with my account?

Disregard the marketing emails.   If you prepared and filed your joint return and it was accepted, then you do not have to do anything else.   Going forward, it is best to stay consistent with which account you use so that you can easily transfer the previous year tax file into the new return.  And...do not change the order of the names on the joint return.