OJS - Reviews are dissappearing when reviewers hit Submit

One journal has had several complaints that reviewers are entering their reviews into the given fields and when they go to submit, the page reloads and is blank.

Any suggestions?

Just adding a bit more context - it appears that this happens when reviewers are working on the reviews in OJS - so the page may be open for an extended period of time and there may be a timing out issue? One workaround presented by a reviewer was to work on the review in a word processor and only use the review page in OJS to quickly paste in the review details. I’m wondering of others have heard of this problem and if it is related to how long the review window is open.