Problem related rent

i rented out my flat on 12/10/2024 with a settlement that the rent will start from 16/10/2024 . the tenant paid the half month rent plus one month deposit . I told her to collect the Keys from my friend ( I am staying in another state . but After 7 days ie on 20/10/2024 , my friemd told me that nobody has collected the keys . Meanwhile my propertyDealer also informed me that he couldn't get the Rent deed signed becase lady is avioding him . i contected the lady and her husband attended my 3rd call informing me that the lady was in the hospital as her heart was 35% working hence she will not be allowed to climb stairs therefore i should refund the full deposit . I told him that after deducting 15 days rent + the commision of property dealer , I will refund the amount but he did't agree . On 26/10/2024 , the lady herself talked to me and assured me that she will live in that flat but requested me to refund the 15 days rent which i denied Now she is niether collected the keys nor