Regretting

Moved in Low Rise 120 End Street Paid deposit,full amount of rent

Fews day later after moving they sent me a letter that I owe over 7k then a week later they switch off my power.

My first invoice of the month still got over charged. I was told it will be fixed and after calling multiple times they informed me to pay the whole or whatever I can afford.How is this acceptable for one to pay something I am incorrectly charged