Forms won’t submit w/ attachments

We use happyforms as a resume submission platform on our careers pages.

As of today, all of our forms have stopped submitting to us. Users receive an error message that their “Response is invalid” and “one or more files are not valid”. The attached files that have failed are .pdf, .docx, and .jpg. We have had no issues with submissions prior to today.

When attempting to edit the form, we are now getting the error “The site is experiencing technical difficulties.” in the preview area.

I have emailed support, but this needs to be resolved asap!