Can You Terminate Tenancy Agreement Early

My father moved out of his apartment because the neighbors are drunk and abusive, he has heart problems, he first moved into the property without deposit, I found him a cheaper place near my house, now his former landlord asks for rent on the old land until he finds a tenant, Although he indicated orally and took 200 for an early release from the rental, Hes now say that the money was for advertising, even if he does it through Gumtree, which is free? Now my dad is stuck with 2 rents and we`re all stressed and upset, it would make a difference if he went to court, because we can`t afford to pay both rents Don`t end your lease because your landlord isn`t doing what he should be doing – for example, if he doesn`t make repairs. .