Clock resetting instead of running out

Hi everyone,

I'm pretty new to chess.com so the answer to this question could be very obvious, so I apoligise in advance if it is. 

I started playing a game vs an oppenent on the 7th of Nov with 1 move per 3 days being our time limit. The game has been pretty slow to say the least but for the latest move they have gone well beyond the 3 day limit. Instead of the game finishing, their clock seems to of reset to 3 days. I've messaged the person I am playing about this but they haven't replied and I am at an ends to understand why this is? Does anyone know why this is?

I know on some chess sites (like redhotpawn.com) there are time banks, which allow you some extra time in case you forget. Does this site have this aswell? If so where can I find it?

Thanks

it's a 3 day per move game, your opponent has three days to make a move , try 1 day per move if you want a faster game.

re ; your opponent has three days to make a move and so do you.

Thanks for your reply lazy_fan.

I understand that they have 3 days to make a move. But my problem is that they have taken longer than 3 days to make the move and instead of the game finishing (because they ran out of time/forfeited) their clock has reset to 3 days. 

Thanks for clearing it up stupidhockeyplayer.

I was thinking that it must be some bs rule like that; it's extremely unfair :/