interactive PDF is no longer fillable

I have browsed through the community here, but have not yet found a suitable topic for my problem.
I don't know what has changed, but before the last update (now 17.3) I could fill the text fields previously defined in Indesign in (Mac) Preview, in interactive PDF. This is actually the way it is meant to be. Now something seems to have changed and it no longer works. Am I missing something or has this simply been removed?
And before anyone tells me that it works in Acrobat, no! You can fill in the PDF there, but at any point, so it doesn't correspond to the specifications of the PDF as I had designed it.