: Try a hard reset through the Recovery Menu (Hold Power + Volume Up).
Black screen, detected as “MediaTek USB Port” or “Qualcomm HS-USB QDLoader 9008”. Fix: Use SP Flash Tool (MediaTek) or QFIL (Qualcomm) with correct DA (Download Agent) and Auth file . Auth files are TCL-proprietary and rarely leaked. Firmware TCL 20B
: Using official flash files to bypass software locks or fix persistent system errors. 5. Conclusion : Try a hard reset through the Recovery
– Look for “TCL 20B stock ROM” on trusted forums like XDA or from TCL’s official service center links. The package should contain: Firmware TCL 20B