EKS Fargate capacity is unavailable at this time.

We have been running Fargate EKS for quite some months. Recently, We've been encountering with the errors "Fargate capacity is unavailable at this time.", and pods remains in the pending state. And, this is on everyday basis and very frustrating. Any idea why this is happening (other than no nodes available in that az).

The cluster is in eu-central-1 ( Frankfurt). The EKS Fargate profile is associated with one subnet (eu-central-1a). We are running like 20-40 pods in that profile. Acc. to amazon fargate quota it is capable of running 1000 tasks (max 4000 vCPUs). But with us Fargate even cannot handle this 20 pods at a time. If we would have known this issue, I'd have thought of migrating to the Fargate and Serverless.

Also, I have also tested if I was not running out of IPs for that subnet (256 in total). I tested with replica set of with around 200 replicas. I see that 50 IPs are still available but still some pods are giving the "Fargate out of capacity error".