You might also want to register your phone number with the telephone preference service (TPS), a national suppression service which should cut down calls of this nature as it is not lawful to make unsolicited direct marketing calls to numbers registered on the TPS. You can register your number here https://www.tpsonline.org.uk/register.
We know that these kind of calls can be distressing and intrusive and you have our sympathy. Please do not hesitate to contact us if you would like to discuss it with us otherwise we’d encourage you to report it to the ICO as notifying them of this kind of practice enables them to investigate and take enforcement action where necessary. You can see the action that has been taken by the ICO here https://ico.org.uk/action-weve-taken/enforcement/.