I'd like to know what my rights are

I've been on L&I since 6/30/17 for breaking my knee at work. The doctor released me to modified duty on 11/13/17.  In October, I was informed by my supervisor that she was expecting me back to work even though the doctor hadn't released me yet.  I verified the issue with L&I as well as my doctor, neither of whom had any documentation about this at that time.  On 11/21/17, I received a certified letter from work regarding the modified duty position; however, they wanted a response by 11/10/17 and it had been postmarked 11/13/17.  Two days ago, I received a letter regarding COBRA insurance, at which I contacted the main company and was informed I had been terminated as of 11/9/17.  I'm now being told that it was because I was not communicating with my employer and that I had refused to come in for duty.