on salomon bindings, theres a screw on the toepiece that makes it tighter or looser around the toe of the boot. click your boot into the binding, and check if theres a gap between the sides of the toepiece and your boot, if there is, tighten the screw so the sides are touching, but not too tight. if that doesnt work, try moving your heelpiece forward 1 click or maybe tighten your din a little. also, when its really cold out (like less than 10°f) then your boot shell gets a little smaller and so do the bindings, so it feels looser.
and if none of those are the case, then theres a chance you need new boots.
heres a pic where the screw is
just to throw it out there...
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