Depends how filter was set up. If you used the downloadable Gentech filter for LG from there website, and did it by yourself, it may not be possible. If it was just removed via ADB, that's another story. If TAG installed the filter, they should be able to allow Text Messaging again. On some devices, where TAG has to install a custom OS, it may be technically possible, but unlikely anyone will spend the time to do it.
It depends on the phone
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