Pip call?

Hi, sent in a pip claim months ago, wrote that I can't talk even on the phone, my previous benefit assessments have been paper based. Someone rang them 2 weeks ago for me to ask for an update they said I'd probably need a phone assessment, it was explained again i can't do that. Yesterday I had three calls from a private number, only two people have it including dwp so likely it was them. They didn't leave a message or send a text.
Will I now fail my assessment? Shall I get someone to phone them again?
I did send evidence saying it causes psychological distress, but it is old as i avoid contact with people but its been accepted before. my GP refuses to get involved in benefits so can't ask them to help. thank you

Thanks Gordon, not sure I'm looking in the right place for the provider, found a map with areas on mine comes under 'independent assessment services' not sure what that means? My support rang the pip line last week, is that the provider?