Non payment of rent

Rent Arrears

Hi,
I have tenants that haven't paid rent for quite a few months and are now over £4000 in arrears.
They are just not paying, not acknowledging the letting agents and refused access for a house inspection.

They have been served notice to leave but this was when 6 months had to be given, so are not due to leave the property until October.

I know that the tenants are not going to pay any more rent, so have practically been living in my property rent free from before Christmas.

I feel like the tenants knew the covid rules and have used them to their advantage.

Any advice on what i can do further would be greatly appreciated.

Thank you