Corporate Leasing I Signed An Apartment Lease In May, Corporate Landlord Still Has Not Signed And Given Me A Copy?

I signed an apartment lease in May, corporate landlord still has not signed and given me a copy? - corporate leasing

Is it legal to change your mind and cancel the lease? The lease was from 09 May-July10. The apartment complex is by a company and companies which have not signed my lease, and not mine, although I have been paying rent since May