Me and my son are new 3D printers. I bought him a Flash Forge Finder... Our test prints went fine. But our first 2 slightly more advanced jobs (like a coffee mug), the print started great, seemed to be cruising, then around 40-50 percent, it started cooling, from 220 degrees to closer to 100 and below, and then the filament becomes stringy (not hot enough I assume). Cannot figure out what's happening? Any ideas? A setting? Something we need to adjust?