Can’t upload a picture anymore

Good afternoon,

Thanks for the awesome plugin you’ve build! It was doing everything quite fine untill a few days ago. When a customer uploads a photo on the following page:

https://www.bakkerij-olink.nl/winkel/taarten/chipolata-taart-met-foto/

Nothing happens to the upload photo button after selecting a photo and my client doesn’t receive the download link in their e-mail. What could be wrong?

Kind regards,

Roy