Rooftop -Excessive mortgage charges

[Jules27]

Hi, was hoping if I could get some advice in regards to charges that were applied to my mortgage after it was passed to another company. I was previously with J.P Morgan who then sold it to Rooftop Mortgage. When it transferred over it was showing that I owed an additional £3500 in arrears. I called them and requested that they show me where these arrears were from. When I received the informational it appeared that they had charged me late payment fees (sometimes twice in a month) for home insurance which they had added to my mortgage when I didn’t send proof that I had my own home insurance. This went on on for over a year, the home insurance amount they applied was £12 per month. There was also no mention of these charges or arrears on any of my statements with Platform Mortgages. Can they do this? *Any advice would be greatly appreciated, thanks.