Inherited tenant issues

[Marco Lopez]

So I just acquired my first property in the Hermosa neighborhood of Chicago. It's a commerical space in the front of the property and legal 2 unit coach house in the back. I inherited tenants in all 3 units and according to the estoppel certificate and the lease it's stated that the commerical tenant is responsible for paying their own water/sewage. 

I contacted them today and he said he's never paid the water bill and the previous owner also told me that the tenant has never been responsible for the water bill.  The lease and estoppel certificate say otherwise. What are my options at this point should I just evict them? I've looked around and cant find any decisive information. Thank you