Fatal error locking out items

[Squishyah]

In two seperate online coop games I have earned the achievement 'fall of the goblin empire' and 'boom'. During each of these two games in whatever stage I unlock an achievement/item a fatal error occurs causing the game to stop and when I relauch the game the progress bar for the unlock is completely full, but no matter what I do I cannot actually unlock the item. This has also happened to my friend once for the trident item. What can I do?

[Zyddie]

Hey Squishyah.

Any chance you have a screenshot or recall what the error said ?

//BFG Zyddie.

[Squishyah]

I don't, but if it happens again I will record/screenshot it

[Squishyah]

So it seems that as I continued to play the two characters that I had recieved a fatal error on the items eventually unlocked at seemingly random times.

[Greenstreet]

Has the error occured again? And if yes, can you send us a screenshot to [e-mail], please?

[Squishyah]

It has not occured again, however I have informed those that I play with and if any of us get the error we will submit a screenshot.