Hello

I have a possible shifter problem

I'm building up a new gravel bike with a Ltwoo R9 Hydro groupset. While indexing the front derailleur I found that the left shifter will not hold the front derailleur in place while spinning the cranks to complete the shift to the big ring. Unless I continue to put force through the shift lever with my hand the tension between the derailleur, chain and chainring is forcing the shifter back into a lower indexing spot, and so the derailleur is dropping away from the chain, which equals no shift.

This feels like a shifter fault to me. My Shimano groupsets will shift to the big ring without keeping hand pressure on the shift lever, but was wondering if anyone has experience with these to say whether this is normal or not?

Cheers