After getting tasks done, you need to archive some lists.
You can recyclearchived lists whenever you need to.
To archive a list, click the gear icon in the top bar of the list and select "Archive".
You should have access to manage the sheet or list to be ablee to archive them.
Click on the toggle button at the top of the page to enter the "Archived Tasks" page.
Then, to recycle the lists, click the gear icon in the top bar of the list and select "Recycle".