The hair could be too long because it is moist from humidity, but more likely it is just too long.
Loosen the screw and remove it so you can remove the frog from the stick. Next put the frog back on (without the screw) and pull it tight toward the back of the bow. If the eyelet goes all the way to the back of the slot without the hair tightening enough, the hair is too long. If the hair can get tight enough the hair is not too long and something may be wrong with the screw mechanism.
Next check the condition of the screw threads, then the eyelet. If all looks good insert the screw directly in the eyelet and tighten to see if it threads all the way in. If it doesn't, try cleaning the threads. If that doesn't help it is possible to buy a new screw and eyelet to install on your bow - but that might cost as much as you paid for the bow.
Unfortunately a rehair will cost more than you paid for the bow.
The only other thing you can do if the hair is too long is consider that "the slot in the stick is in the wrong place" and decide whether you want to risk the bow by trying to extend the slot further back. Consider your options and what you have to lose.
I have had similar problems when a bow (rehair) was shipped to me from a location with different climate conditions than my own.
The "pencil rule{ for hair standoff from the stick is just a guide. For different bow stiffness and cambers the best standoff may be different. If the torque you apply to tighten the bow feels normal before it reaches the "stop" this might just be OK for this bow and if it plays OK just enjoy it.
Col Legno bows are very nice.
Andrew Victor offers good advice, go through these stages of checking the bow.
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