Momentum Bad Sevice

Good day

I have a 3rd party claim in against 1 of Momentums customers

I was involved with a car accident = I was standing at a red robot, when a taxi skipped a red robot and hit a Nissan Livinia and then the Nissan Livina hit me, my car got damaged and had to get towed away, it is not my fault that the taxi hit the Livina and the Livina hit me, now Momentum does not want to pay out my third party claim - but according to me - the Nissan Levina is responsible for the damages to my car and they must sue the taxi = now they are rejecting my claim - what am I to do? I do not have money to pay for my vehicles damages, I was going through a bad divorce at the time, and could not afford my own insurance = please can anybody advise or assist me in what to do to get Momentum to pay for my damages = my vehicle was also towed away from the scene, so its now at First Helps assessment yard - this is the very first time in my life that I was in an accident = I am honestly desperate to get this sorted out = Please can anybody help me