Entries not saved

We have an application form on the website that usually works but this week we sent a lot of candidates to it, we had not entries at all so I contacted everybody back and most of them said they filled the form but on the backend there are no entries at all…
I cleared the cache which seemed to help and received one application, but everything should be set so I don’t have to do that everytime.
Didn’t seem like I had that problem before, could someone help? Maybe another plugin is blocking it?

The page I need help with: [log in to see the link]