[SOLVED] Prints no longer sticking to plate, don't know what else to check

[scuac]

Since I received my printer a few months back, I have been successfully printing since day 1 (aside from a couple of support fiascos). I printed less than a dozen things with it, then I stopped for a couple of months. Yesterday I tried resuming printing, but it seems that nothing is sticking to the plate anymore. At first I thought it was the model I choose this time, but I tried printing the Elegoo rook and that failed as well, since then I have tried:
- Re-leveling the plate (didn't seem like it needed it)
- Tested the LCD (all pixels light up, with the full test, not the built in hollow rectangle one)
- Increased bottom exposure from 60s to 80s (although that has never been a problem)
- Room is at 72 degrees and resin has been in there all the time
- Inspected FEP, found no issues, and cleaned it with IPA
- Added painters tape to the screen
I am using the exact same resin bottle as before (which is not expired, good until 04/21), I have let it sit to make sure there are no bubbles. But even after going through all of the above I still get the print stuck flat on the FEP. Is there anything else I am missing?

[cliffyk]

I think you will find the resin is "good 'til 04/21" if not opened. That may not be the case, however I'd try some new resin and see if it makes any difference.

You may also want to try roughing up the platen with a scotch brite pad or some 600-800 grite wet sanding paper (do it with "wet"). I found that to greatly improve plate adhesion on my May of 2020 model M20Silver200401 machine.

[scuac]

I think you will find the resin is "good 'til 04/21" if not opened. That may not be the case, however I'd try some new resin and see if it makes any difference.

You may also want to try roughing up the platen with a scotch brite pad or some 600-800 grite wet sanding paper (do it with "wet"). I found that to greatly improve plate adhesion on my May of 2020 model M20Silver200401 machine.

Yes, it might end up being the resin simply went bad. I replaced the FEP with a brand new one today and still having the same issue.

[scuac]

I think you will find the resin is "good 'til 04/21" if not opened. That may not be the case, however I'd try some new resin and see if it makes any difference.

You may also want to try roughing up the platen with a scotch brite pad or some 600-800 grite wet sanding paper (do it with "wet"). I found that to greatly improve plate adhesion on my May of 2020 model M20Silver200401 machine.

So, I tried replacing the resin with new one, no luck, still sticking to the FEP.

Next I tried your advice (cliffyk) to use a scotch brite pad, and I also re-leveled the plate one more time (but this time I really loosened up the screws a lot, very wiggly). And now things are working again! I am not sure which of the two things I did was the deciding factor, but I am happy that this got resolved. Thanks!

[cliffyk]

Great to hear you are "up and running".

Most likely it was roughening up the build-plate surface. It is too glossy from the factory...