I use Tetra, but any solid grease would do it. A sample of SIG grease usually comes in a box with the new gun.
When I really want a slick rail, without using real abrasives, I buff it with a patch of lead removal cloth (the thick kind like Kleenbore). The patch will turn black, it is normal. Then rinse it off with some solvent or alcohol, wipe or blow it dry, and dab it with grease.
Also -and I don't remember if it applies to the 2022 - some SIG's have asymmetric recoil springs. In that case be sure the front end is in the front.