Constant "no number calls" since moving to IP Telephone from landline (Home) (Resolved)

2o Sep2022. I was called by virgin media today and had a very frustrating conversation. The net result was “we” cannot see these calls which are affecting your phone number so you can block nuisance calls or change your phone number. This is just wrong on so many levels. I tried to explain that this was potentially a network attack on the mail servers that are computer generated against random numbers and that, without appropriate investigation, how do VM know where else in their system is affect/attacked. I suggested it be passed to the cyber security team to investigate and was told basically they were too busy to bother them. Just change you phone number and thanks for calling us. One month, several hours, meaningless conversation and no result. I suspect the call is now closed.