The Utorch SF-01 has a so-called 10-tap system identical to the one of Streamlight.
With 10 taps you get from one “program” into the next “program”. See also Link.
The three available programs are: - high/strobe/low, - high only, - low/high
Could it be you are stuck in “high only”? And you have to 10-tap your way out of it?