My phone cannot connect to my computer via USB anymore, as in the drop-down option does not appear at all. I've reset my computer, reset and wiped my phone to factory settings, but to no avail. I have tested it with numerous USB cables, and they all seem to only charge the phone, not put it into USB mode. I have downloaded and installed the drivers multiple times on many computers. I have tried with debugging enabled and with out Can anyone be so kind as to give me some advice, or what steps I can take myself to fix this?