が止まりません

won't stop; cannot stop

→ が
phrase Common #5,118
won't stop; cannot stop Used when something continues without stopping. The noun or activity before が is what will not stop; 止まりません is the polite negative form of 止まる.
JA: ジョニー君は廊下で座っていましたが、どうしても笑いが止まりません。
EN: Johnny was sitting in the hallway, but he just couldn't stop laughing.

ジョニー君は廊下座っていましたどうしても笑いが止まりません

Johnny was sitting in the hallway, but he just couldn't stop laughing.

くしゃみが止まりません

I can't stop sneezing.

鼻血が止まりません

My nosebleed won’t stop.

せきが止まりません

I can't stop coughing.

出血が止まりません

The bleeding won’t stop.

が止まりません

I can't stop crying.