Okay continue to use symmetry.

Confirmation of the previous step revealed OH of intermediate products near the wall at around 330 microseconds.

After that, the flame appears to spread from the area where OH was observed.

As for temperature, the lower side extends toward the wall from around 370 microseconds.

Are there any other results I should check?

Also, do you have any ideas to solve this problem?

Maybe it was a bad idea to coarsen the non-center mesh near the wall in order to focus on the center of the wall.