I have had 8 good prints until my Snapmaker unit died with white screen of death / freezes. What you describe sounds like either a calibration issue or a temperature issue. Are you using PLA?
For Calibration, use the piece of paper that came with the snapmaker. Calibrate each of the four corners, in order like this: Start with position 1, lower the print head until the print head “snags” the paper so that a GENTLE touch can’t move the paper out of the print head. Check this by moving the head up 0.05mm and the paper is released, so then move it back down 0.05mm so the paper is “grabbed” by the print head against the build plate. This is your calibrated position. Press 2 and repeat this all over again. When the paper is grabbed at position 2, then press 3 for position 3. Repeat again and repeat again for position 4. With the paper grabbed at position 4, save the calibration.
Next, use either raft or brim to start your print job. You’ll use a little extra plastic, but it is worth it. I’ve had great results with both.
For PLA, I use 200 degrees hot end, 50 degrees heated bed. If you might have gotten oil from your fingers onto the print surface, clean it with a little bit of rubbing alcohol. If you aren’t using PLA, then you will need to use temperatures that are compatible with what ever you are using.
Using one of the default profiles / settings from the Snapmaker 3D application should be a good start.