I get same problem halfway or later in cycle, but it's only cause of not rotating. It's from the area not healed and getting sore and repeated injections will start causing pain and soreness.
Simple fix.
These areas give enough rotation.
Upper thigh
Lower thigh
Venoglute.HIP
Delt
Triceps in rear solf area relaxed below shoulder
Then glutes of coarse
I have both sides of body of all these I usually only need to do my glutes, hips, and lower thighs that's it on short esters.
Stop jabbing, find area press one hand pulling skin tight other in pin push pin point against skin and turn back and forth so it sinks. This in these areas works for me. Heat gear up in body of syringe until a couple drops come out of needle from gear expansion. DO NOT GET NEEDLE WET UNDER RUNNING WATER. I always pass a alcohol swab over needle and let dry first. I always pin after shower and use alcohol over area first.