ESA computer system and payments

I had to phone the DWP this morning and my ESA payment was missing. The same happened two weeks ago. Last week I also had to phone in again the following morning as the payment was still missing. This time the payment was made within four hours.

The DWP phoned me back to tell me that they were making a payment. They said the reason for the failed payments was the size of my file on their system as my claim dated back seven years. Please can someone tell me if this is a common problem? I am sure I am not the only claimant who has been claiming for that length of time.