¶ 1. The gap between the platform and the release film is too large.
Re - level the platform with a piece of A4 paper (Reference video: https://youtu.be/kQ0yooRZ6d0. In the video, a calibration card is used for leveling. It is recommended to use A4 paper in actual operation). Pay attention to locking the screws diagonally. After leveling, slowly pull out the A4 paper and feel the friction of the paper. If the friction on one side is very small or almost non - existent, it means the leveling is not done well and you need to level it again.
If the problem cannot be solved after proper leveling with the A4 paper, you can try to level it without the A4 paper.
¶ 2. The screws of the molding platform are not tightened.
After leveling, make sure to tighten the screws of the molding platform in a diagonal order.
Increase the initial exposure time and the number of layers. You can set the initial exposure time to 60 seconds first. If the printing is normal, you can gradually reduce the initial exposure time to shorten the printing duration.