(advice Requested) Duplex Tenant Disputes

[Nathan Fisher]

One set of tenants moved to a nicer place I own. Now new and old Tenants are arguing. There's issues over the shared washer dryer, semi shared storage space, there's dog poop involved, and a missing coat.

Most posts say to just ignore it and let them figure it out, but both tenants have been great for years, and I pride myself on maintaining a great Landlord/tenant relationship. It's critical to my business model, and it allowed me to come through corona with 90+% of rent paid on time.

I have a plan, but i'd love your advice. What are your thoughts? How can I be the best mediator and get these people to behave like adults?