DWP Compliant Interview

My friend had a visit from dwp compliance visit,she provided her driving license and a bank statement,she is on ESA ,the reason they called out to her was because something came to their attention,as ESA is a taxable benefit the tax office were doing random checks they found she'd had a payment from ppi and the dwp were notified,everything was resolved and they told my friend nothing would be done as it was an error on behalf of the other parties,they said she had a payment of £9000,she only had a payment of £250 which she provided evidence.so I really wouldn't worry x