Well, I have now exactly the same problem, printouts just stopped sticking to the bed. I have two big squares on the film instead objects printed on the bed. I guess print fails at the first bottom layers. I did a calibration with 2.2.3 firmware. Today 2.3.0 firmware showed up. I will calibrate with 2.3.0 standard procedure and retry. Hope not to crack the screen
Another problem is that I need to wait around 5 hours to verify if the calibration was done properly. Maybe there could be a faster way to verify the calibration?
Update 1: I noticed that the bed in fact can / should be pressed down at two marked points gently down until it sticks to the film. Instructions says to keep those two points but I think they should be pressed. Will see the results in around 5 hours
Update 2: Some parts now stick to the platform but some does not. It seems that print fails now at some later upper layers because I can see smaller sticked objects on the film that resemble individual printouts in shape. There are imprints left on the film even under those elements that were printed. I guess I have to push the platform even harder down to the film. Will try and report back. Firmware does not seem to affect this process (2.2.3 vs 2.3.0). Maybe this is caused by some table plate adhesion degradation over time? I did not have this problem before and I did calibration several times.