Switching from mobile phone to zoom on a different phone

I have 2 users in my company who were using company cell phones. We ported the cell phone numbers to zoom so that they can continue to use those numbers in the zoom app on their personal phones and not have to carry around two cell phones.
Contacts from the company cell phones show up in their zoom mobile apps on those phones but not in the desktop app.
They are unable to see the contacts stored on the company cell phones in their mobile (on personal phones) or desktop apps.
I somehow need to get the contacts that were stored on their company phones into their zoom accounts so that they can view them in the mobile app(on personal phones) and desktop app.
They were both using company iphones and use personal iphones.

Can anyone help?