Incorrect charge for notice?

[StJamesInfirmary]

I signed up for a service, paying a monthly fee with a minimum 4 month commitment. Stayed beyond 4 months. Eventually decided to cancel. Checked Ts&Cs and the only info about cancelling was to get in touch with the provider. I messaged the provider who confirmed it was cancelled and no more money would be deducted. A few days later a monthly payment was taken (over £150). I assumed it was done in error so messaged the provider again who eventually replied saying it was my notice period.

Just checking if they're allowed to do this given that there is no mention of a notice period in the terms and wasn't mentioned when I cancelled either? Is anyone able to point me to guidance on this? I've had a quick look but can't see anything.

Bump

They can't charge you for fees that aren't mentioned in the T&C's. Ask the provider which part of the T&C's or contract allows him to make such deduction.
Download a copy of the T&C's for yourself before doing so.

Thank you. I didn't think so but not 100%. I will ask

This is not a fee that isn't mentioned in the T&Cs, however. This is to do with the notice period. If a contract does not contain a specific termination clause, there is an implied right to terminate with reasonable notice. The argument here is about the notice period. OP believes she should be able to cancel instantly, the supplier thinks there should be one month's notice.