How do I stop a homeless person’s benefits from coming into my account?

This whole situation occurred in England where I attend university.

Back in early December, a homeless person (X for short) I’d previously talked a couple of times to approached me. X told me they could not access their bank account (I don’t remember exactly why) and hence couldn’t receive their benefits. X asked me if I would be okay with calling DWP (the department for work and pensions) with them, and switching their account information to mine so I could receive X’s benefits and give it to them in cash. Being on friendly terms with them, I agreed under the condition that this would be a one-time occurence (they assured me they would have their bank account sorted out by the time the next payment rolled around.)

After receiving the benefits and giving X the money in cash, I put the situation out of my mind and a couple of days later traveled back home to Bulgaria for the holidays. Meanwhile, unbeknownst to me, every two weeks X’s benefits continued to be sent to my account – apparently they hadn’t sorted their account out.

Fast forward to a couple of days ago, when a British costudent of mine, Y, messaged me saying X had approached them and asked them to get in contact with me regarding their benefits. After checking my bank account and seeing the further payments, I asked Y if they would be alright with serving as a middle man between myself and X so I could get their money to them, after which I intended to call my bank and tell them to stop accepting payments from the account that was sending the benefits to me. Y agreed and gave X their money, but after calling both my bank and DWP I’ve been told it’s not possible to stop the benefits from coming into my account without X’s details (which I don’t have) and permission – in fact, X needs to call them. With the Covid situation being what it is, I have not returned to the UK and am likely to remain home for a while longer. It’s difficult and time-consuming to get in contact with X, and I’d much rather avoid further dealing with this situation.

Can my bank really not block an account from sending me money? What are my options? I’ve been advised to contact the Citizens’ Advice Bureau in conjunction with Y. Anything else I should do?

Thanks for reading.