Having issue with my gas dryer that will not start.

I try to turn it on a few times and each time has a different result.

1st test - Press the start button and it worked. (I stopped it after a few minutes, not sure how long it will run)
2nd test - 1 minute later from the 1st try. Makes a sound but does not work.
3rd test - Open the front cover. Press start button (does not work, unless I manually spin) the drum. Then it works. Flame doesn't stay on. Smelled burnt.
4th test - makes buzzing sound. Even after trying to manually spin it. It does not work.
5th test - no sound or working (the 5 test took between 15-25 minute period)

The next day. Tried again. Does not work on 1st test. But does work if I manually spin the drum. But stopped after a minute.

Any idea what is broken?

Thanks