Tenant has not signed Renewal lease

[Brad Brubaker]

I have a tenant that is coming up on their 1 year lease.  The lease is good thru December 14th.  I sent them a renewal lease about a month ago.  They keep telling me that they are going to stay but still have not signed the new lease.  This is my first year in business and not sure what to do if the lease is not signed by December 14th. Any advise would be appreciated.