Unum denied my claim for not returning to work after 3 days when they had already approved 3 weeks

I contacted Unum for a short term disability claim in April 2016, this claim was approved and I went about my business as usual. I went into surgery on 5/10 for a removal of a cyst on my right ovary. The doctor gave me a three week recovery time and on my follow up appointment on 5/19, he said I was on track to return to work on 6/1. I asked the doctor if I could go back earlier, to which he replied No I would rather be safe than sorry. Give yourself this time off, it has already been approved and there would be paper work hoops to jump through in order to go back early. Because of paper work that hadn’t been completed at that follow up appointment (my fault for not remembering) I didn’t return to work until 6/3. I’ve been fighting for months with Unum bouncing back and forth between Kelsey and Unum. Unum needed medical records they faxed Kelsey Seybold, Kelsey said they needed payment for the medical records, they faxed Unum with no reply, Unum said they replied with no response from Kelsey so I had to call Kelsey said they need a check and not a credit card number. Why was it my responsibility to go back and forth with these companies for months? This has been very stressful, not to mention when they finally DID get the records they denied my claim saying I should have been back to work after 3 days! That’s ridiculous when they had already approved 3 weeks off for recovery. I appealed and the doctor contacted Unum and again said I needed the 3 weeks of recovery. unum denied my claim and said I could seek mediation or file under section 502 of yada, yada, yada. I believe they just don’t want to pay me for the week off and dont think I will take time to pursue any further since it’s only about 500$. I’d like to know what my options are. How they approve and then deny coverage after the fact!