Yes they do
Depending on what manufacturer or model you have the appropriate firmware may or may not be available. In most cases it's pretty straight-forward to look it up and I would recommend just swinging by to find out. Some independent repair shops have stopped offering this type of IMEI Repair service because it's akin to modifying a serial number which can be kind of shady, but it's a little more invasive because it's the identifier that is associated with billing and activation of a device on a carrier's network along with the hardware radios in the device. Regardless though, always worth finding out if it a service that is available and most shop have the capability if not willingness in some cases.
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