Lloyds bank - consumer protection s73?

viio11

Hi

Just spoke to the bank and they say that apart form the statements which they have for the last x amount of years they do not have a copy of the agreement where I have signed and agreed to have this account with my ex - do they have to have a proof i.e. copy of it to prove that I have signed up to that overdraft and agreed to it?
The guy on the phone was verging on being rude and just said you opened this account and therefore you must have agreed to it but we have no copy of that agreement?

thanks so much for your help..