Play around with Z-offset a bit - from your images you might be slightly too high (but I am not sure, your first lines look just right). Also, make sure the bed is really clean - use dishwashing soap and/or isopropanol. Since you already had one good print, some dirt might be the reason. If nothing helps, you might be part of the bad-printbed-club - several threads on this in the forum, e.g. this one: Please give us the 11 x 11 bed calibration with heated bed! and several others. If your SM 2 is still within warranty and you can see your bed is really bumpy, try Snapmaker support, they may send you a new build platform.
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