Services/boxes to unlock devices.

[wee2000]

Hi all, is this the right platform/thread to ask for methods to unlock?

We trade alot of used mobile phones. Whenever we got telco locked products, Usually, we just sell the devices as it is. As time passes, we now would want to acquire some unlocking tools ourself. But wanted to know what device/boxes/websites should we refer to? as an example, for today, we have 5 devices that needed unlocking

1. vivo x90 pro - there is an app from operator which blocks most of the functions of the phone. Can't enter menu, we can't even master reset it, as the options is grayed out. But the phone doesn't have any user locks, still can sign in to play store, can all in/out.

2. Sam Z fold4/oppo a78/reno7 z- Has an operator notification. The phone is not locked now, but we want to know how to unlock it, in case it gets locked in future.

3. Sam s21 ultra - SIM 1 was not detected, SIM2 works fine. Could the SIM1 be locked to telco?