forgot to protect deposit

Tenancy Deposits

I have an exemplary record in paying back and protecting deposits.

But on this one occasion i forgot ( so many things going on inc caring for dying friend and moving to spain)

After 10 months i remembered and protected the deposit and when i sold the house, i returned the full deposit to the tenant.

6 Months later the tenant has threatend me with court for " compensation' for late protection.

anyone else had this experience and what was the outcome ? 

Surely the courts would take into account my perfect record and the reason for forgetting ??

Thanks in advance