Per Pianotuna, "Hi, His problem may be the Heliotrope controller. It was once state of the art, but unfortunately time has passed it by".
In my view, far too little system info provided here by tpi except to conjecture (Solar variables are many). The Heliotrope 22b is essentially of BlueSky 2000e MPPT design, with merely an added bell or whistle (and longer warranty...). Helio's were built under BlueSky 2000e product licensing. The BlueSky 2000 MPPT (though minus computer interface) is still a viable product and well proven single-stage controller.