So we've been having this problem as well, and while this fix works for us -- what's causing it to become unchecked in the first place? We're definitely not going in and changing anything, but within the past few weeks, it's come unchecked twice! We have no idea when it happens until our customers start telling us they didn't get their usual attached pdf! While this fix is quick and easy, knowing when we need to go and change it would be a huge help! (As would not having to go and change it period, as it's March 2021 and this problem seems to have originated back in November 2020.)
