@Maria14475 I would decline for several reasons:
1. Stays over 30 days probably make you a landlord without a lease. You could get a squatter.
2. Longer stays may result in lack of payment. A guest complaining may hold up your pay out and ABB will not release. I think only the first 15 days are guaranteed but others who do long term can chime in
3. The guest is an unknown quantity with no reviews. If you are a new host you may be targeted by scam guests because they will hold you hostage for those first few reviews.
I would say "thanks for your interest but I am not accepting long term stays at this time." And set your nightly stay length to 2 weeks or less. Long term stays on ABB are incredibly risky.
ETA-- I see you ARE a new host. Yeah, just take a hard pass on this one. And it might not be a bad idea to ask for a listing critique in the New to Hosting forum. There are some definite tips and things I see right away that could really take your place to the next level. Its cute!