PPL PRS Legit or not?

Hi all, the internet seems a bit vague so thought I'd ask the collective here if anyone has any experience of pplprs.co.uk

I know of PRS for shops, bars etc but we are a small company (4 employees in total) and out of the blue this company has phoned trying to sell us a music licence.

I smell a rat as they seem to be trying to sell me something that I don't think we need. We do have a radio in the office but my understanding of PRS is its only needed when you are broadcasting in public? Customers do sometimes visit but we aren't a shop, just an office and warehouse.

Any help would be appreciated.