Windows .BAT 文件 CALL 命令语法

Question

call :ddbackup     "%%A" "%%B"
The syntax of the command is incorrect

call ddbackup     "%%A" "%%B"
'ddbackup' is not recognized as an internal or external command

:ddbackup

这个标签是存在的，因为我可以

goto :ddbackup

帮助!!!