1. Add backpack grids: You can get more backpack grids by completing tasks, opening treasure boxes or holding more items in other ways.
2. Sell unwanted items: For those unwanted items, consider selling them to reduce the burden of backpacks.
3. Use the storage box: In the game, there is usually a facility called "storage box" where players can store some items to save backpack space.
4. Make bigger backpacks: Some games allow players to make bigger backpacks through the manufacturing system to accommodate more items.
5. Unload some items that are not commonly used: If you are sure that some items are temporarily useless, you can consider unloading them to reduce the burden on your backpack.
The above are some common solutions, and the specific methods may vary from game to game.