Demand for payment from bank for letters

[Nical]

After a separation and later divorce, my sister-in-law had sole ownership and responsibilty for the marital property - this meant having a small mortgage. It took a while to sort this all out. For a few months various different sums were paid then it went on to a direct debit which has been paid every month. Last week my sis-in-law got a phone call to say that she hadn't paid in April. When she asked why the bank were phoning in late August, she was told that this was because she hadn't responded to four letters.These letters never arrived. Having ploughed through a huge pile of paperwork, she's willing to accept that she does owe this £120. However the bank also want an additional payment of £140 - £35 for each of the letters! Can they do this?

[ummmm]

Yup..

[craft1948]

When I was chasing people for money I had to send correspondence by recorded delivery to prove receipt...........don't they do this anymore?