In this case @damir.davis!
You can do something like I do using conditionals and leave it marked in the button element that the button is not clickable, you will do this in the conditionals if it is met it will be clickable again, you don’t even need a workflow, or you still have the option to force the input not to move to the next field without filling it in, then just select in the input option (element) this input not be empty (these are options). Below is the print.