Desktop contacts not synced with android app contacts

My desktop contacts are not synchronised with my contacts in mobile or web version.

For example our company has 43 users - all are visible as contacts when in android version or web version, but I only see 13 of those in the windows desktop version.

Has anyone had this issue before (and how did they resolve it)?

I initially had a free version as an individual, and then we created a company and did PABX integration (and enterprise licenses), so not sure if that influenced it in some way.