Landlord Says I Can't Break Lease One Week Before Moving

Location: North Dakota

TLDR: Landlord ignored my lease termination notice and is threatening I can't leave until July.

Hello, I am a PhD student and a couple of months ago I was informed there was a high likelihood I would lose half my pay (I make like $4/hr). Because of this I started looking for more affordable housing and was incredibly lucky as I ended up finding an amazing spot for half my current rent. I signed my current lease in July and very clearly remember the landlord explaining how breaking the lease was a simple process and I would only need to submit a 45 day notice before moving out.

My lease specifically has a section outlining the process of termination and explains how I must give them 45 days written notice and nothing more. I've broken a lease twice before and never had any issues. I sent the notice middle of December once I decided I wanted to officially apply for this new more cheaper apartment. I sent an official termination email and followed up multiple time (5 or 6 different times through email, text, and phone calls). I never got a response or answer and this was strange as I had previously ALWAYS received a warm and friendly response.

Well, my move out date is next week and they finally decided to answer my call. Here's where it gets confusing. First they said they never received anything. Then they said they received a text (the text explained everything) BUT not a voicemail (???). Then they said they found the termination letter but it wasn't done "the correct way". They're now saying it had to be hand-written and given and hand delivered to their office. But here's the craziest part, this apparently doesn't even apply to me because now they're saying my "lease hasn't matured". I'm very confused, and panicking at this point. They're saying because I've only been at this apartment for less than the full year, I can't break it. They then proceeded to very patronizingly explain what a lease is and how it is "a legally binding agreement" yeah no shit, I'm breaking the lease.

No where on the lease does it say I am locked in for a year. Why would the lease contract have a section outlining how to terminate it if I supposedly can't? I'm already going bald from grad school stress and I'm really struggling how to handle this. I OBVIOUSLY wouldn't have signed another lease if they had explained this prior but they ignored me. Any help is greatly appreciated!!!!