Accident question

i was in a small accident in December have dash cam video showing not my fault... well I get notified today it’s being held as my fault with the company I work for... they say in the video they see me using my cell phone in reflection of window which is bull! What they see is reflection of my dash cam.... I can see what they see and it looks like a cell on the dash of the truck but later in the video if you go frame by frame u will see me with my phone taking photos and also see what they called my cell in the reflection... they told me it was my final write up which I have never had a write up! So how can it be my final?? They also said I couldn’t dispute it because they didn’t have that available for their drivers anymore... I am on probation for a year for something that wasn’t my fault! So now if they find something to let me go it will be on my record and no one else will hire me! I have 23+ years of driving with no accidents in the last 15! Now this what should I do? If I lawyer up I prob will be fired. I can show the video but it has to be watched on a computer to see it doesn’t show on a phone

 

They are desperate for drivers so not trying to replace me they have people quitting left and right.... but seriously thinking of hiring lawyer to get it removed do not like a tarnish on my record esp since I have proof it wasn’t my fault even accident report states not my fault

 

No driver facing camera what they saw was a reflection in the window of my truck and assumed it was my cell phone which it wasn’t it was the reflection of my dash cam facing the window