Refund of Token Money

I received Rs 190000/- as token money from buyer on sep 2020 with a deal to sell my house at 53 lakh, after 3 months they said they don't want to go ahead with the deal started asking for refund of token money. There was property broker in between who told them once new deal is finalized we will return your money. Now til date house is not sold, may be due to covid slowdown. There is no written record for all this. Also one month , the buyer started negotiating and demanded for price reduction..I reduced the same by 2 lakh but still they wanted it further down. Now they have started harassing by calls to refund the money and also asking for interest. I (seller) have however told them to stay patient and give me time for another six months till Nov 2021 and even if till then house is not sold I would arrange someway and would refund the token. I have now told the buyer to give me writing that they have canceled the deal, then I would decide further and try to return money. However they are pressurizing and not ready to wait..what shall I do, shall I file case ...forfeit the money , return by deducting or refund the whole amount or should also take broker in picture and file a case...please suggest..