If you would like to set up the regular closed or day off
Please check the following step and set it by iPad.
Settings > Business Settings > + New
Edit the name and leave it blank in Business Hours
Scroll down and mark the dye that you want to make it closed regularly
Press the orange button < Business Settings go back to the previous page to save your settings. And check if you make the setting successfully.
In the future, when you suddenly want to close a specific date, you may add it to this module.