Transferred money to wrong account

ellyfish

Hi! 
So, my boyfriends, Dad transferred money into my boyfriends ex-girlfriends account by accident (used to be their account pre-split). They have tried contacting her numerous times and she is completely ignoring everyone. We have tried contacting the bank but they said it's a tricky and lengthy process to get it back and there is no guarantee of even getting the money back at the end of it. I apologise if this isn't your bog-standard post on here, I'm just pretty angry and at a loss at what to do! Does anyone have any advice on ways to deal with this? 
Many thanks! 

eskbanker

He (not 'we') needs to contact his bank and invoke their misdirected payments process - it can take a few weeks but is dependent on cooperation from the recipient.

https://www.fasterpayments.org.uk/consumers/what-happens-if-i-have-sent-payment-wrong-place

If she isn't responsive to that, or informal attempts to contact her, and the amount is worth chasing, then pursue her via Money Claim Online....

https://www.moneyclaim.gov.uk/web/mcol/welcome