Scaling in AKS is one of the easiest things to do. All you need to do is go to Azure Portal, find your AKS instance, and click on the Scale blade:
Once there, you can change the cluster capacity depending on your needs.
Make sure you have the required number of nodes available for your application—such information can be found in the Kubernetes dashboard. If you don't have enough machines, some of your images might not be deployed.
