Linux Bash Clear Command Not Found

Hi, I made a simple menu that allow selection of Imaging images and I have
errors about the "clear" command. My script show many menus systems and I
have to "clear" the screen everytimes. But it say when I run my script:

Clear: command not found

I don't understand. the CLEAR command is built-in linux, perhaps the path
of where this command resides must be set. One thing: when I type CLEAR
in prompt, it works.... weird

thanks!