Can’t delete Sales tab or any item in it.
OK I realise that the Sales tab is where the tutorials place their results so the tab must exist.
I must have done the same tutorials twice as it has made another set of sheets with a digit after the name.
Sales1
Sales2
each with another sheet with exactly the same name:
service id
service id
On my screen it looks like this:
Sales1
service id
Sales2
service id