Numbers not allowing permission on own files

Hey there elleyne119,

Thanks for reaching out to the Apple Support Communities. For the best steps that can help with managing the permissions for the files on your Mac, check out the steps listed in this link here that can help: Change permissions for files, folders, or disks on Mac - Apple Support

Assign permissions to users and groups

1. On your Mac, select a disk, folder, or file, then choose File > Get Info.

2. If the information in Sharing & Permissions isn’t visible, click the arrow .

3. Select a user or group in the Name column, then choose a privilege setting from the pop-up menu.

- Read & Write: Allows a user to open the item and change it.

- Read only: Allows a user to open the item, but not change its contents.

- Write only (Drop Box): Makes a folder into a drop box. Users can copy items to the drop box, but can’t open it. Only the owner of the drop box can open it.

- No Access: Blocks all access to the item.

You can undo any changes to privilege settings for a user or group in the Sharing & Permissions section since opening the Info window. Before closing the Info window, click the Action pop-up menu  at the bottom of the window, then choose “Revert changes.”

Let us know if that's able to help.

Take care!