I do not own your printer but I print a lot with abs on a glass bed. First question comes to mind is did PLA print correctly after changing the bed?
The Z offset which is the space between the bad and the nozzle when the first layer is being printed needs to be sufficient for the plastic to come out when printing the first layer. This offs set (distance from glass bed to nozzle tip) will be different if you are using .2mm layer or . 5mm layers so set it once with a piece of paper may not always work. When doing this setting with the paper, you may want to heat the nozzle, back out any filament and wipe the nozzle clean so you get an accurate measurement. You may also want to heat the bed to 110C before as the bed can expand and move closer or farther from the nozzle compared to being cold.
When switching filament types I always flush the nozzle with eSun cleaning filament, then flush the cleaning filament with the new material (about 200m worth or print will delaminate if not fully flushed of cleaner) I would also assume you meant 240C on the hotend temp not 140C.. 240 should be fine, I typically use 235 for my printer but 240 will be fine.
So in conclusion my guess is you either have a clogged nozzle or the bed is too close to the nozzle (Z offset/starting height is insufficient)
This assume PLA does not work.. if PLA does work, crank up the bed temp to 110 and see if the pla works.. or inversely try printing abs if that that is already loaded with a cold bed and see how that layer looks..
Good luck!