I've recently received a letter from a supplier's solicitor that I must pay for services that I've already paid for. What action should I take to resolve this?

If your supplier has got their solicitors involved then you should take action as soon as possible as if you don’t respond they might start a claim against you.

Firstly you should write to both the supplier and their solicitors advising that you have already paid for the service and giving them proof of how and when you paid.

You should ask them to contact you before taking any further action but can also assure them that if they do issue a claim against them then you will be defending this.