#asknostr is the best hashtag to ask for help. What app are you using?

nostr:note13uvlhpu8pnr9kc46wykhrldgay9up4dnt8lqaeu52xddltspqdgs8c559f

What web page? There's a ton of different Nostr apps you could be using. Did you log into the page using your nsec? Or did it have you set a PIN when you logged in and it used that PIN to encrypt you nsec, so it now always needs that PIN to decrypt it to sign anything?