Streamline Theme – Only allow one accordion menu item to be open at once?

[alyrose]

Currently in Streamline theme it is possible to have all accordion menu items expanded at the same time.

How can I force an accordion to close as another one is opened?

[alyrose]

Thanks for your reply. I tried it but it just stopped any accordian item from opening when clicked. 
I asked ChatGPT if it could amend your code to fix the problem but it did not work either.

Any ideas on how to resolve?