Just tried deleting my account--got exactly that error. That's not reassuring
From 2019: https://www.reddit.com/r/Lastpass/comments/afmfop/cant_delet...
From 2020: https://twitter.com/jowouters/status/1222438393981886464
There's a ton of those posts. Some in the official LastPass forum as well, and the response from LogMeIn was basically that the account was deleted.
(It's of course crappy, just saying that this behavior is nothing new and probably just something they don't care about enough to fix..)
I stopped using LastPass a long time ago, but this has definitely put them on thin ice for me, I won't be recommending them going forward.