The number 020 3946 9300 is a pay support line run by Comensura, a payroll company in Bedfordshire. Their pay systm is called CNET and they run the HR and payroll for a number of established companies such as the British Council.
If you receive a phone call from the number 020 3946 9300 it may be because you have raised a support ticket with the team. Fell free to answer and get your query dealt with.