Welcome to the community!
Sorry to hear that you were the victim of a scammer, it's a relief to hear that you managed to stop any bank transactions in time. When we call you or when you call us we would always need to pass account security with you using 3 random character from your memorable word. We NEVER ask for card details. These scammers use general internet issues and vague descriptions to try and secure trust with people to prove who they.
I would highly recommend changing your passwords on a device that was not used for them remote access and taking the advise that @nodrogd has mentioned, getting an expert to check it out or completely reformat it back to its factory state to start again and reporting this to Action Fraud.
If you ever doubt that you are not speaking with a genuine employee/customer service agent from any company, always hang up and call the customer service number available on the companies main website.
Please let us know if you have any further issues or concerns and we'll be happy to help.