Am I as landlord reponsible for a deposit?

Tenancy Deposits

One of the letting agents I have used has just gone bankrupt. The agents who have taken over his business have informed me that the tenant's deposit will have to come from my pocket(she is vacating the flat to re-locate). The new agency will not cover this cost itself, even though I have so far done it the goodwill of continuing to allow them to let out the flat for me. The deposit in question goes back to the days before deposit schemes (I need to check this to be sure). I would like advice on this and whether I have any redress or none at all. I can always take my business elsewhere or manage the property myself of course. Thank you.