If you’re having some trouble getting parts to stick to you removable build plate here are some tips:

Smooth Build Plate (PEI)

The smooth build plate is recommended (by Prusa) to be used with PLA
Is not recommended (by Prusa) to be used with material such as PETG without some form of release agent or something to slightly lower the adhesion eg. Windex
When removing prints printed with PETG be care not to rip the PEI as you flex the build plate.
A wipe with Isopropyl alcohol is recommended before every other print or acetone every 10 prints or so to rejuvenate the PEI and remove and build up from previous print material (Use acetone at your own risk, not to be used if you are concerned about warranty of the plate and or machine. Acetone is a poison prolonged direct skin contact, fume inhalation or use may lead to illness.)
Brims are recommended if possible to prepare the nozzle for printing. If you cannot fit a brim within the build area the default purge line should be enough.

Textured Build Plate

DO NOT USE ACETONE ON THE TEXTURED PLATE AS IT MAY DAMAGE TO POWEDER COAT CAUSING IT TO FLAKE OF THE BUILD PLATE
Thoroughly wipe the plate with Isopropyl alcohol before each print to maximize adhesion
Be sure not to print to close to the plate as it may damage the surface, if damage occurs it is not covered under warranty for Prusa
If you are struggling for adhesion try to increase the extrusion rate/multiplier to press that material into the texture further without bringing the nozzle closer to the surface
As last resort you can gently roughen up the surface with some fine grit sand paper (300+) but this is not endorsed by Prusa and may void the warranty of the plate