Closing a joint bank account?

Okay so this isn’t in relation to me and my boyfriend, just him.

He had a joint bank account with his ex as they lived together (they broke up around 2 years ago and we have been together almost 1 year). Long story short they’re only just getting around to closing the joint account it.

She told him she called the bank and they said they both had to go into the bank and close it together even although there is no balance or direct debits, is this true?

It does seem like they would both need to sign something but she’s tried to trick him into seeing her a few times and he’s too laid back to realise so I guess I’m just making sure she’s not up to her old tricks here. Thanks!