It’s most likely ‘just’ the hose was originally slipped onto a nipple whilst warm and when cooled
There should not be air getting all the way up the ‘ribbed nipple’ to arrive at the arrow mark
There won’t be much to be done other than cutting the hose shorter and making another connection - which is bound to be too short and also less likely to get a good seal
If it’s new then go back to the retailer, the line may get exchanged
Whats the pressure range at that point?
HPA isn’t to be sniffed at; but the ‘high’ is relative and the risks relate to the incoming and outgoing pressures.
eg airsoft / paintball cylinders fill at 3000psi or 4500psi
Have a leak at that pressure going to skin contact is nasty, and a sudden burst can send cylinders flying (there’s also something much more dangerous when shortcuts are taken when filling)
Old school cylinder regulators dropped pressure to 800psi to 850psi
More modern ones could be half that up to around 600psi/650psi
You still don’t want that on bare skin and the cylinder can still be sent off spinning
Inline regulators then come down to the lower hundreds of psi
It still needs respect
If it’s not new then consider buying a replacement hose or if confident about constructing a replacement hose
A potential bodge is to ‘aid it’ with some heat shrink
Cover the joint as well as you can, then warm the hose in warm water.
Press it forward and then cool it
(The hope here is to get back to the best seal)
Make sure it’s fully dried
Get some heat shrink, long enough to go back up the hose and onto the fitting - but not so far enough to effect the join
Gently warm the heat shrink evenly
Note that you’re trying to hold your original hose well rather than gaining any extra seal, but the shrink helping to hold in place as you guide the hose around your RIF
(((Note that you lose any warranty and it could fail again later)))