Resetting/releasing a used phone from GDMS


No it is not lock up. It is: factory reset and auto reconfigure. This is common and very useful situation when you have hundreds or thousand phones.
Seller have all tools for setting device to factory settings. Grandstream have no tools to check if one phone was sold or steal or whatever.

Ps. Seller also should know password that is set after factory. With all this i would return device to seller as broken or not useable.