Have capital gains from a K-1 from my non-res state (AZ). Because it is on my fed ret , the gain is flowing to my res state (MT) ret and can’t figure how to delete. Help

The capital gain income that is reported on your federal tax return would also be listed on your Montana return. To avoid double taxation that may result from this, look for a credit for taxes paid to another state on your Montana return. When you complete that section, any tax you paid in Montana on the capital gain income taxed in  both states will be subtracted from your Montana tax so you don't get double taxed.