Everything looks fine at the beginning of the level. The further the player goes, the worse the graphics are.
I don’t know how to fix it. Save the graphic as png-8? Or maybe there are too many sprites?
The problem is on Android, the pc version is ok.
Do some checks for backgrounds use at max size of 2048x2048 greater sizes can be even not rendered in older devices, png8 is ok but compressed with some compressor like RIOT or https://imagecompressor.com/
For pixel art Nearest is the best for vectors Linear is the best
Make sure you have enabled the option smooth images in your project properties or in Resources option one by one
If after the check is still happening look closely your event maybe something is not working as expected in your events.
Although the image was not large, the sprite that was tiled was too large. Thanks