What controller is it? I know that the second generation of Xbox one controller’s analog stick sometimes doesn’t work with in Destiny and that can disable sprint. Otherwise check the controller’s configuration, both in Destiny’s menu and the controller’s specific app. Maybe something was remapped accidentally?

Gameplay (your fault) In the last couple of weeks have you started using new armor or changed up your mods? Check your mobility. Is it low? There's a chance you ARE running but your mobility is just trash. Settings (also your fault) Check setting to make sure your controls haven't been remapped. If I was trying to troll a room mate or sibling, that's where I'd start; works every time. Also sometimes custom settings are reset to default during a Tuesday reset (so maybe not your fault, but it'd be funny if you trashed a perfectly good controller for that) Used Controller (also your fault) You have to wonder why someone would sell a working controller f or less than $2 at GameStop. Seriously, stop shopping there. I can't think of anything else. I can only hope a bunch of other people are having the same problem, because otherwise it's probably not something bungie can fix on their end.