SLA printing: piece does not stick to supporting structures I am trying to print a box shaped object with an ELEGOO Mars SLA printer. I positioned the piece rotating it on X and Y axis 35 and 30 degrees. 
However, the print fails because the piece does not stick to the supporting structure (see picture). 

Do you think that it could be a problem of the piece sticking to the display due to overexposure or deteriorated film? Or is it something else? 
I tried two prints, lowering the exposure time from 8 to 6 seconds, the second print still failed but at least the piece is not totally stuck to the display. 

Any other idea?

First failed print with 8 seconds exposure: the film was completely jammed and all the resin was stuck there (this is why there is no piece on top of the supporting material)


Second failed print with 6 seconds exposure: the film was perfectly clean, but the object did not stick to the supporting materials therefore collapsing. 



This is the 3D drawing
I have tried to print the piece upside-down with the cave part facing down and it worked.
Since the printer prints upside down, positioning the cave part facing up creates a suction-cup effect on the printer display that makes the whole structure stick to the lcd and detach from the supporting structure, thus making the print fail.