Mechanical failure

I do a good pretrip it’s in a non visual area, it’s worn but not leaking yet. Make a few 90* turns (I left a customers yard it was tight) drive three miles and air is bleeding off while I look for a place to trim it and tighten the fitting back up.
its junk rubber hose they use in these trucks. My plastic airlines I had an issue one time when it was -15 outside.
Between the fittings coming loose and the lines ripping I fix them several times a month.

 

They use bulk rubber hose and won’t let me put plastic lines back on it. I literally unscrew the fittings, cut the airline 1inch and put the fittings back on. Exactly the same as the shop as done numerous times.

 

I don’t think I’ve been that bad of a driver honestly. I do my pre trip, I’m on time, I drive safe. Maybe I’m wrong tho

 

What am I supposed to do? They refuse to switch the lines back to plastic ones and every other time I’ve managed to fix it in a parking lot.
It’s ripping INSIDE the compression fitting?
1 time it happened on the street like I said it’s never happened like this.
The line has slack so it SHOULDNT be happening.

Edit: the only way to check would be for me to unscrew the compression fitting after every time I’ve made a 90* turn.
Like I said maybe I am a bad driver but I don’t think so.
ive only ever scuffed a bumper on dirt, had a mirror chipped by another driver, I rubbed a sign with no damage when I was fresh out of school. It’s not like I’m out playing crash up derby

 

It’s an issue with the fittings, the original fittings were replaced before I got the truck. These are brass fittings the shop put on. There are sharp edges.
The places I go i have no choice but to make a 90 to get out. It’s tight.