In the past, Workshop Software wouldn’t sync over customers who had bad formatted phone numbers. Once the initial sync occurs, it will only check customers who have been changed/updated in MYOB since the last sync.
There are 2 resolutions to this issue:
1) Update your customers in MYOB so that they sync over. Please note: this might be a little tedious, so it may not be the best option. However, it could be a quick option if you need a specific customer now.
2) Contact support by emailing email@example.com They will advise you to re-sync your MYOB. Once you do this, your customers should come over.