Select input, selected option left empty empty

Hi,
On my website I have ring sizes for customers to select. I am using “Select input” for this. I left “selected option” blank. It used to be that it was set up like it worked so that nothing was selected where now the first option from the drop down is selected. I also have “required” field checked but now that does not make any sense since first option is selected any way and if the customer wants to buy they can do that without really specifying the ring size.
Do I need to change the settings? Or did something change in the code so it does not work any more? Could you please look into this? Thanks.
Kind regards

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