9.33" Android Radio for Mercedes Benz M Class W166 ML250 ML350 Touch Screen Compatible with Wireless Apple Carplay Android Auto,Car Stereo Bluetooth Navigation GPS (W166+NTG4.5+9.33in+8GB+64GB)

Was missing screws to put plastic cover on hardware bracket. The instructions are not clear. 21 tiny pictures that take up a third of one page with instructions that say generic things like "docking snd inserting cables" along with a 1" low resolution picture. I have it installed and I cannot get the Bluetooth sound to come for my stereo. If I try to make a call using the Bluetooth, the radio keeps playing and the person on the other end cannot hear me. I am sure I hook something up wrong, or there's something in the settings, but the instructions are so bad I don't know where to start