Possible Harassment by apartment neighbor

Location: Missouri

I think my neighbor that my apartment shares a wall with is harassing us. I've lived in this apartment Since April 1st and have received 4 complaints about a strong marijuana smell from my apartment from this neighbor. I have only smoked marijuana in this apartment once my second day here and even then we had a fan blowing the smoke out the window. She was pounding on our door in no less than 5 minutes after my roommate and I were done.

On April 29th we received a notice from the property manager of a marijuana smell which was ridiculous because since the first interaction my roommate and had started going outside to smoke. There is a designated smoking area near the apartment that we walk to or if there are kids nearby we walk to my car and smoke with the windows open.

In May we received no notifications or complaints.

Towards the mid/end of June we had friends over for a game night and a police officer came by and asked to come into the apartment for another marijuana smell complaint. We let them in and said they were welcome to sniff around. All of our legally bought marijuana was sealed in smell proof bags and we hadn't smoked yet either.

Today, July 20th I received another text notification of yet another marijuana smell complaint. I know for a fact that neither my roommate nor myself smoked in the apartment last night.

I will say that we do smoke flavored marijuana vapes occasionally in the apartment, but we always have a fan on to help dissipate the clouds they give off.

I'm at my wits end and want to know if I can legally start a case for harassment.

What can I do?