HTC ONE ( AT&T) stuck on htc logo screen/bootloader

A

AC Question

Hello,
My phone has been working fine al along until this morning when I woke up.
I got a text message and i decided to open it, but the messenger app could not open. So i decided to restart my phone but i accidently tapped on "airplane mode". So hold my power button to turn to turn it off. While it airplane mode was turning off, it said "preparing sim card" and i immediately restarted my phone. After that happened the phone restarted and was stuck on the HTC logo screen. I then went into bootloader and it says ***tampered*** and ***locked***. I tried to factory reset/recovery but nothing happens only ***security warning*** shows up.

As of now, im so confused because i have done nothing to my phone since i bought it. I also bought it new. I tried to contact HTC support and they told me it could be a thrid party app or a virus so i have to send it in for repair. If i send it in for repair i wont get it free because of the ***tampered***. but i absoloutely did NOTHING. I dont know why its like this. Can anyone help me please? Im desperate because right now i do not have the time and money to get a replacement phone because i am very bus. Thank you

Sorry for my bad english >_> its not my first language, thanks!