Modifying a Lease: I Was Moving Out, Now I Can't

My question involves landlord-tenant law in the State of: Michigan

I initially need to have the lease modified where I was no longer apart of that lease, things have changed before the new lease was signed and I can't leave any longer. The new lease doesn't have me on it but hasn't been signed be me or any of the other tenants.

Which lease is valid, what do I have to leverage with a new person now taking my spot but with nothing signed. What are my options how do I get back in the home?

Thanks in advance!

Modifying a Lease: I Was Moving Out, Now I Can't