Can't delete Sales tab or any item in it

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

Hi,

Any tabs except the one named “Start” can be deleted. Do you see any system messages after you try to delete a tab?

If not, this sounds like you are currently not logged in as SYSAdmin in your account (perhaps this is the reason for the other mass delete issue too). Could you make sure you’re logged in as a SYSAdmin user in your account?

Thanks,
Jeff