1981 Mercedes W123 280e m110 I6 - Refuses to start

My 1981 Mercedes W123 280E refuses to start, the car cranks but never idles, when I crank it and press the gas paddle it shows sign of firing but never fires. It has been doing this for about 2 weeks now, at first, I thought it was cold start issues as this model is notorious for that but I tried it during the day and still nothing.

I haven’t had any issues with the car before so this is a bit weird to me.

any ideas on what might be the problem?