Ah no, we do not
We need all the details you can share to get an idea of what goes on.
Now you say the phones fail to provision, here's a couple of things to check:
1. Make sure you haven't got any blacklisted IP entries in your management console. This blocks provisioning.
2. Check whether you have DHCP Option 66 or equivalent on your network. It can throw things off if misconfigured. Turn it off during troubleshooting via your DHCP server.
3. VLANs can also cause serious problems in case something changes you are not aware of, or a slight misconfiguration. But since you use them they should also be considered suspect during troubleshooting at least. I might not be able to help on this specific subject other than provide very general advice.
4. Try from scratch: delete a single phone from an extension and then factory reset it. Make sure the bold entry is "Rejected" from the Phones page, to see if a fresh one will appear after the phone starts up. Select it and click "Add Ext." to create a new extension. See whether this one phone comes up ok and depending on how it goes, we can see where we go from there.
