T41G WiFi cannot access web gui

[ufo]

We have brand new install of Verizon VOIP with Yealink T41G phones.
We cannot access the Web gui for the phones unless we do a factory reset. If we do a factory reset, the phone will not provision service because the autoprovision setting is blanked by the factory reset. If we enter https://yealink.sipflash.com into the autoprovision settings, confirm and save settings (that is the only setting we changed), the phone reboots and provisions phone service. Afterward when we point our browser to the phone's IP address to access the web GUI, it says "Page not found." I have confirmed we are using the correct IP address and can ping the phone. The phone appears in the router's Dhcp table. What is happening in the provision process that locks us out of our phones? Also the Admin password gets changed to some unknown password. As a result we cannot configure the phones with custom rings, paging groups or any other useful features. it is really not practical to do a factory reset and re-enter ALL settings every time we want to change one feature setting.