WhatsApp showing contacts not in my Google account.

Hi folks,
I have a really weird problem that I haven't found a solution to so far.
In my WhatsApp contacts list I have some contacts showing up that are NOT in my google account.
When I try to delete it it says "the contact to be deleted has details from multiple accounts. Details from read-only accounts will be hidden, not deleted."

I have the contacts set to display ONLY my google account contacts and/or with WhatsApp contacts.

How do I delete these from my contacts list in whatsapp?

Thank you for your help.
ker