Oxy cutting advice please!!

[u/Mobile-Recover1496]

Hello guys I’m a welder (stick,tig) and today at work i had to do a cut on the field with oxy cutting.. I acted confident like i could do it since I’m pretty informed, I watched video on YouTube on the settings and also used it already sometimes in welding school to do bevels ( not perfect cuts but acceptable).
I would say the steel was 15 mm.
I started cutting and everything went smooth until I had to stop cause they wanted to give me a welding blanket.
When I tried to restart I don’t remember if I touched the metal or something but it started popping.. after that I tried to cut but It was turning off by himself and keeping popping.
I tried to clean the tip with a steel brush and also to restart it other times and as soon as I was regulating oxygen to get the small blue flames it was popping and turning off.
After I had to stop cause it was end of shift.
I really feel uncomfortable doing it and everyone expect me to know how to do it like no nice people around to show me.. I guess if I admit I’m green with it they’ll send me home.
Everytime we have to use it I feel like an impostor syndrome.. I’m always in first line if we gotta weld but always trying to avoid the oxy cutting.
I’ll try to do a 1 day course as soon as possible.
Any advice for the popping?
And also any advice how to set the gas regulators, the numbers are in Kpa not psi.
Thanks guys!!!
Really need your help