I'm getting form entries with a blank in what is supposed to be a required field??

I’m having similar issue and checked all three columns. All Text. The 3 fields are First Name, Last Name and Email. None of which should be difficult. I’ve tried Chrome and Safari browser and iPhone Safari browser. All error the fields and prevent me from submitting. However a couple entries have gotten through (1 of 20 so far). I’m expecting 1,000s so I need some help.

Thoughts?