Release phone from Zoom to upgrade firmware

[jamesmknox]

We recently got some Yealink T33G phones, all in great shape. One of them, however, was apparently used with ZOOM. The firmware is rather old, and has problems with our network (drops the connection randomly and reports Network Unavailable). Yealink's newest firmware fixes this problem - BUT, we cannot upgrade the firmware. It is apparently "locked" somehow by ZOOM (according to Yealink). Yealink says contact ZOOM, and ZOOM will apparently not respond unless we have an account.

We did fine an FAQ on ZOOM that said the problem could be resolved by logging in to your ZOOM account and deleting the device. But again, no account.

A full reset to factory defaults works fine, but does nothing to solve the problem. The upgrade to the current Yealink firmware starts, and then a few seconds later the link to the T33G web page returns on the PC, and the phone stays stuck in "Upgrading Firmware."

So hence my plea. Does anyone know a solution. I would hate to toss a perfectly good phone, but right now it is not usable by us. Any switches or buttons or chips in the phone that would help? Any magic handshake or other spells we can cast on it to TRULY return it to original values? Thanks