Aracauna and Barred Rock not laying-Why?

[10happychickens]

We have 10 chickens total and all are laying except for two. The araucana is 6 1/2 months old and she has layed one egg, almost two weeks ago. We also have a Barred Rock hen who hasn't layed in quite some time now. She is over a year old. Both chickens seem healthy, happy and are not moulting. Any ideas????

 

[Annabella]

They seem to go off the lay. Hard to say why .
Others are suggesting that at the moment it could be the heat??