Is your 3D print lifting off of the bed during a print? You need to get your 3D print to stick to the bed. First, make sure that you are working with a leveled bed. Once you have done the paper test to make sure that the bed is level and the nozzle is the proper distance from the bed you need to ensure the bed has proper adhesion. I normally use Aqua Net hair spray. I preheat the bed to 55 degrees and then I spray a light coat of hairspray directly onto the bed. This usually does the trick. You can also use Elmer’s glue stick, but I think the hairspray works best. Once you have your filament sticking to the bed make sure to read my suggestions for really cool things to 3D print. I do all my printing on one Ender 3 V2 and two Aquilas. If you notice that the glass is getting a thick film you can remove it and wash it under soapy water. Once dried you can place it back onto the bed and apply a fresh coat of hairspray. Hopefully, this helps get your 3D print to stick to the bed.