Clash of Clans Won’t Let Me Upgrade Walls – Says Maxed Out, But They’re Not

I am having a major issue in Clash of Clans—the game won’t let me upgrade my walls, even though they are not at the max level. Every time I try, I get a message saying “You have upgraded the maximum number of walls”, but I still have unfinished walls that need upgrading.

Why is this happening? Is this a bug or a restriction in the game? I need immediate support to fix this problem because it’s stopping my progress.

Supercell, please resolve this issue or at least explain why I can’t upgrade my remaining walls. If there’s a limit, players should be informed properly. I appreciate your help and look forward to a solution!