Where can I have the internal battery replaced on the Nintendo DS?

Moin moin friends, I recently have a nintendo ds again and now I play with GBA that problem is that the internal battery is used up. I can continue playing but time does not go by. For example, at Pokemon there are no berries growing and at nintendogs I go for a walk 5 days later and it means you are just starting out for a walk. Now wanted to know where you can have the internal battery replaced and whether it is worth it or how much it costs. Doing it myself is tricky.

This is not the internal battery of the DS, but that of the games. They have a lot of games to be able to save them or so that the time in the game can progress.

You can change them yourself if you have a soldering iron, otherwise I wouldn't know where to have them changed. Maybe ask at a shop for video game buying and selling.

Media market or gamestop? Something like that do you mean?

Media Markt less, maybe gamestop and if there are other buy / sell shops besides gamestop, try it there too.