how to add a fieldfrom hidden to default subpanel

Hi ,
I have created a project called “implementation” and under the project tasks I have created 4 subpanels and now i am adding the 5 th subpanel to the project task from hidden to default . but it is reverting back without adding when i press the save and deploy.
Can any one help pls as this is urgent fix.
Your help is appreciated.

What version of SuiteCRM are you on?

Hi ,
My version is 7.8.2