High bill after moving house

I was paying £26.50 for the ?vm125 package before I moved house. Virgin said my first bill would be £116.50, which I queried.(I actually went through this process 3 times because virgin kept presenting the bill of £116.50) I could see I was being charged £54 a month now. The payment date was changed too. Virgin said a credit would be applied to the account so I would continue paying £26.50. But the bill was still £116.50 even after a credit of £62.50 was applied. I found it really confusing, but I changed the direct debit date back to the original 22nd so I could see easily what I owed. The bank cancelled the £116.50, and I made a one-off payment of £26.50 for September + £20 moving fee. So I feel I’ve paid the correct amount.