cracks in terra cotta arch

[bartlebooth]

Hi, I am new here but can use some advice... our Forno Bravo Casa 80 oven was built in October, I went through the 7-day curing process and was able to start making pizzas in November. A small crack developed in the front arch but it didn't seem too much to worry about. However, after a harsh winter I made my first pizzas last week and the crack has spread and now looks much more worrysome. I have attached a few photos here. Any advise what I should do about this? I'm hoping it can be patched without having to remove the outer stonework (which would be quite expensive). If so, how should this be done (what material,etc.).





Thanks for any suggestions or advise.