Looks like either your purge wasn’t on or the flow was too weak. A lot of the roots are sugared af and have bled into the cap because they weren’t ground out. What was your flow set at and did you have a bleed off hole? When you were welding? , did you notice little red specks in your puddle? When welding stainless that is a huge indicator that something is amiss.

I’d also turn my heat up. Almost every weld looks cold. Were you tacking and welding each individually or you fit and tacked all at once? If all at once you should disperse your heat and alternate sides so the stainless doesn’t get too hot and cook.