Great comments, but Id like to add bit more.

Start with calibration if you havent already:

1. e-steps calibration - do it once after any hardware change
2. Temperature tower - every filament is different
3. Flow tower - do it every time you notice extrusion issues after changing filament
4. First layer calibration (bed leveling and nozzle distance) - you obviously did that, but look if there is any room for improvement
5. Retraction calibration - not relevant for this model, but thats the last part of basic calibration

On top of that, you want to improve 1st layer adhesion to avoid lifting:

1. Use brim
2. Add more squish (reduce nozzle to bed distance)
3. Print first layer slowly
4. Clean your bed and dont touch it with fingers
5. Use round corners when possible
6. Dont use part cooling fan on first layer
7. Leave bed heater on for some time before you start printing (to give enough time for build plate to heat up evenly)
8. Lower bed temp after first layer (example: I print PLA on clean glass at 60C, but after first layer I drop it to 55C)
9. Use mouse ears (basically a fat brim that you place manually on sharp corners)

Use glue or hairspray if nothing else helps, or consider better build plate like PEI or even better quality filament