Unum keeps prolonging the process to approve my LTD benefits

I have been waiting for UNUM to make a decision on my long term claim for almost two months. They constantly keep prolonging the process and approve my long term benefits. Instead of requesting my medical records all at one time, they come up with something every week of what they’re needing. I was told a decision would be made within 4-6 weeks. It’s past that time frame I have not received an approval decision. I was recently diagnosed with Spinal Stenosis and cannot perform my regular job duties. I sit for long periods and physical strain on my body will aggrevate the condition per my doctor. I am without any type of income because of this issue. I really need help. I don’t know what to do nor do I understand the process and turn around period for long term disability to be approved.