In Handyman Office, the map control is using OpenStreetMap as the map engine.
It uses the http://tile.openstreetmap.org/ URL to get the tiles for the map.
For the zooming functionality, Handyman Office uses 3 subdomains from the gsgroup.io domain on https (port 443)
These are:
atile.gsgroup.io
btile.gsgroup.io
ctile.gsgroup.io
If you are having issues with the display of maps in Handyman Office, make sure that you can access these URL`s.