Refuse to refund deposit

Me and my brother both rented a flat with Jolian Properties. Due to my brother losing his job he had to give notice. All off a sudden Jolian Properties came up with a lot of stories not to refund him his deposit, after being harrased on whats app for a month to pay his rent my brother borrowed money from my dad which is a pensioner to cover his last month of rent and to give the 20 day notice that he will be moving out. Up until today no refund has been made to my brother. And now they use the same story with me - full of excuses. We have done everything by the book and still no refund. They dont even answer my emails. But when we had to pay up the deposit to move in they were fast on demanding the deposit. By law we must be refunded if there are no breakages or damage to the property. Maybe they can't afford to pay us back our deposits and no one wants to rent in the complex where we have stayed. Jolian Properties are sharks and *****ing honest peoples money. I will not leave this here, we want our deposits back.