I had done the same, 1 month on, 1 month off. The whole time my numbers were in line with what they should be, I dont know what causes it to be honest. I feel like the wave I am currently on is going to last for a while.
One thing I noticed, and I think has really helped me out overall is light meditation. Nothing crazy, chanting or anything, just basic breathing exercises. When doing this I found that the relaxation released pressures in my pelvic area aka Pelvic Floor. While doing the relaxing/breathing I felt blood flowing to the penis, did some research and found my pelvic floor was always tight, or seemed to be always tightened. Relaxing of this area has restored spontaneous erections, and even helped relieve stress.
Sleep plays a huge factor as well. As we know T is produced by the testicles while we sleep, so poor sleep will get you poor T levels. But since we are now on TRT and provide our own T, this shouldnt matter, right? Wrong, sleep is still a HUGE factor in libido. Even though the T issue is resolved, there is a lot more to libido that just T. Sleep is needed for the brain to send them love signals to the proper places. If the brain is tired and distressed due to poor sleep, it wont happen. I've got a appointment with a Sleep Study Dr this month, I snore loud since starting TRT and think I may have Sleep Apnea. The wife has videoed my snoring, woken me up and I swear to her I am not even asleep. The strange thing is I dont feel like I am sleeping when this happens. Will be posting results after the study.