Challah rolls open up when baking in the oven

I cook Challah rolls very often.

Sometimes it all goes great. Some other times I encounter an issue I cannot identify where it comes from.

The baked challah roll comes rises in the oven and opens up in a not very nice way. Taste is great, but the look is obviously not very good.

Here is a picture. That crust kind of opening where the roll is folded is the issue I am dealing with.