HELP! It's auto flowering, but the flowers aren't coming out. Help!!

[LaVince]

It's auto flowering, but the flowers aren't coming out.

The cycle of light is 18/6.
It's been 54 days since it sprouted.
The other kind has been blooming for a while now.
But the other two plants are still unflowered and only grow tall. (I've never grown this big during auto-flowering.)
Isn't it auto-flowering?
Should I change the light cycle to 12-12?
I need you to tell me how to solve this time?

[Rwise]

I would go for the 12/12 cycle, my bet at this point is you have photos and not autos.

[SoOrbudgal]

I agree with Rwise you have a set of stubborn autos or photo plants. Give them 12/12