My best guess without be able to see the issue is that the memory assigned to PHP is being exhausted. Here’s a link to an excellent blog post that covers several different methods on increasing this limit. Which method that will work for you really depends on the host. I suggest starting at the top and working your way down the list to see if one of them resolves the issue for you.
If that does not work, then it may be some type of plugin conflict. I suggest temporarily deactivating all unrelated Connections plugins. Likely the issue will resolve at this point. Activate them one at a time until the issue returns. When the issue returns, the last plugin activated was the conflict.
Let me know what you find out. Hope that helps!