After receiving SSDI, Reliance Standard delayed their payment adjustment and I can't get a hold of my case worker.

I had both shoulders replaced in 2012. Reliance paid my STD and have been paying LTD for a year. Once I was approved for SSDI I sent them my reward letter and payment amount. I did not receive back pay due to the fact it took them 3 months to approve me the first attempt. They did not make a payment adjustment once they received the information from SSDI, now they want me to pay them for over payment. I have tried and tried and tried, get the picture, to get my case worker to call me back but she will not. I have not heard anything from her except I am waiting on your Dr., I call the Dr. send her everything she needs. and still no contact. In Sept. 2013 I again sent them my SSDI info and now i have not received any money and was told by Customer Care Services that my continued Disability has not yet been approved. I thought it was harder to get SSDI than LTD…