Sofirn if25a won’t turn on

Might be hard to test but I would suspect the possibility of cracked solder on the brass button contact or perhaps something on the board itself (on the other side where you can’t see without disassembly). In this post there are some borrowed pics of the driver…looks like a lot of potential for issues with hard drops: [Review] Sofirn IF25A flashlight: $34 (discount code available) with 21700 cell, 3800lm, USB-C, Anduril [pic heavy] - #39 by 80T

I’d make sure the tail spring is still snug and where it needs to be, too.

If nothing else, Sofirn is usually really good about sending parts (or sometimes an entire new light). If this model driver doesn’t show up in their aliexpress listing for drivers, just message them and they can let you know a price (would assume this one might be a little more expensive). Changing the driver isn’t too hard but will of course require working from the front end of the light, desoldering the led wires, removing the switch (no desoldering there), and poking the driver out the bottom using a pick/probe. Fiddly, but if you can do basic soldering of wires to contacts, not a bad job to do.

Oh, also, check the positive end of the battery to be sure that it didn’t simply crush inwards and can’t make contact…doesn’t look real plausible with the giant brass contact pad on the driver, but a simple inspection to do.