Lynnwood gave good advice.
SSDI is a process of denial and 2/3s of the first applications get turned down. The rate is even higher on the 2nd application but on the 3rd, 2/3s get approved. I was turned down even though I was quadriplegic at the time with little hope of walking again. Same thing 2nd time but then I got an attorney and got approved, with an apology from the administrative law judge, for not approving the first time. Make sure you use an attorney who specializes in SSDI.
Frustrating but it is worth trying. As I recall, you have 60 days to appeal otherwise you start all over again.
Hang in there and try again with an attorney.