[Q] [HELP NEEDED] Stuck in TWRP without backup topic

I was trying to update my LG G3 to lollipop with root using the video LG G3 - How to install Android 5.0 Lollipop (Root Users) -by Explore Gadgets

It got stuck going to a back screen that says "[780] Fastboot mode started", so i restarted the phone and held down the power button and volume down button to try to go to TWRP, but i had to factor reset first. Then it took me to TWRP somehow my backup was erased so now I am stuck. I tried to download the stock firmware but it doesn't match the BIN. (I noticed a section that has June-19-2014 but my SWV says OCT-...). I've checked everywhere for the same file but an unable to find the correct stock. I have the LG G3 32gb att. I also tried this video How to Unroot/Unbrick LG G3! -by zedomax , but there are too many links that dont fit my phone. Also another weird thing is my phone is supposed to be D850 and there are multiple stickers that say D850 within the case, but when i ran the LG flash tool it tells me that i have D855.

PLEASE SOMEONE HELP! I feel absolutely helpless, no video has helped, and I don't know anyone IRL that could help. :crying: I use my phone for everything in college (alarm, texting, calling, calculator, etc.)