As I see this bug has been reported before for wappler 5
But still the same error on wappler 6. When you try to rename a sub-table says Nothing to do.

As I see this bug has been reported before for wappler 5
But still the same error on wappler 6. When you try to rename a sub-table says Nothing to do.

What type of database are you using and how did you rename the sub table? Maybe you can add a step by step reproduction of the problem.
Over table properties sub-table only change the name.
First

Then

The indicator for a pending change appears.

Then apply database changes.

And get this

Hope this is more clear.
MySQL database on local server.