My work place says one thing and insurance company says different. Fmla problems..

employed at Wal-Mart.
All criteria was met to qualify for fmla leave.
HR never attempted to get in touch with me regarding the leave until a month after it had begun.
Wal-Mart HR tells me one thing
Sedgwick tells me something different. Leave company said i could take my 12 weeks off by working 2 weeks then taking off 2 weeks since it was unpaid. HR at my workplace confronted me for first time a month after leave began and i was set to take my next 2 week leave and told me i couldnt do that and my leave was over and closed since i returned back to work. I would have taken it all at once if that was the case. I don't know if my workplace is correct or if sedgwick the insurance leave company is correct. Please help..