Please Help – 1 AST but some tenants have not been paying?

We have been landlords for almost 15 years – specialising in students. There is always one AST for 12 months (we have no HMO licence and do not need one right now). We have never encountered any problems. We are good landlords, all paperwork is always in order and all repairs are done immediately (within 24-48 hours), so often our students come back after they did their working practice for a year.

Last summer – due to Covid – students’ demand was very low, and we decided to rent the house out to a group of young professionals, on the same 1 AST basis. Two of them working, two of them not, so these two had guarantors. Their AST expires on 31 July.

Since November there have been some problems with rent payments, but generally, after much chasing, the payments have been received. Since March the situation has changed and despite chasing every day and offering them to design their own payment plan – the money has almost stopped coming. We involved guarantors – one is reluctantly paying the longest debt; the other – after initial contact – got completely quiet and does not reply to any correspondence. We chase regularly, both the tenants and the guarantors. The Leading Tenant function is practically not working, all of them pay individually indeed via the leading tenant, but in “how they want and what they want” manner. We reluctantly accept that because otherwise, we would not have received any payment.

The situation with payment is now as follows: 1 tenant up to date, 1 with 2 months debt, 1 with 3 months debt, and one with 4 months debt (that one has the guarantor who does not contact us). At the moment there is zero contact with them, they simply do not bother to reply. We really do not know what to do – we have never encountered such a situation.

Their AST expires soon (less than 2 months), they are moving out and we are worried that we will be left with quite a large sum of outstanding debts, unable to recover that from the deposit. The rent and the deposit are roughly 25% below market rate – due to lack of interest last year. We are not able to write that off – so what sort of legal remedy do we have? How could we make sure that the non-payers get CCJ? We of course will not provide references, but what else can we legally do?

Any advice would be highly appreciated. Thank you very much in advance
Whiteskifreak