What happened?
Did you expect to see some different?
How to reproduce it (as minimally and precisely as possible):
Environment
Prometheus Operator version:
Insert image tag or Git SHA here
Kubernetes version information:
kubectl version
Kubernetes cluster kind:
insert how you created your cluster: kops, bootkube, tectonic-installer, etc.
Manifests:
insert manifests relevant to the issue
while running kubectl create -f manifests/

Insert Prometheus Operator logs relevant to the issue here
Insert Prometheus logs relevant to the issue here
Anything else we need to know?:

As the quickstart mentions, you need to first create the contents of the setup/ directory.
This issue was fixed after adding below CRDs.
Link : Helm fails to create CRDs
kubectl apply -f https://raw.githubusercontent.com/prometheus-operator/prometheus-operator/release-0.43/example/prometheus-operator-crd/monitoring.coreos.com_alertmanagerconfigs.yaml
kubectl apply -f https://raw.githubusercontent.com/prometheus-operator/prometheus-operator/release-0.43/example/prometheus-operator-crd/monitoring.coreos.com_alertmanagers.yaml
kubectl apply -f https://raw.githubusercontent.com/prometheus-operator/prometheus-operator/release-0.43/example/prometheus-operator-crd/monitoring.coreos.com_podmonitors.yaml
kubectl apply -f https://raw.githubusercontent.com/prometheus-operator/prometheus-operator/release-0.43/example/prometheus-operator-crd/monitoring.coreos.com_probes.yaml
kubectl apply -f https://raw.githubusercontent.com/prometheus-operator/prometheus-operator/release-0.43/example/prometheus-operator-crd/monitoring.coreos.com_prometheuses.yaml
kubectl apply -f https://raw.githubusercontent.com/prometheus-operator/prometheus-operator/release-0.43/example/prometheus-operator-crd/monitoring.coreos.com_prometheusrules.yaml
kubectl apply -f https://raw.githubusercontent.com/prometheus-operator/prometheus-operator/release-0.43/example/prometheus-operator-crd/monitoring.coreos.com_servicemonitors.yaml
kubectl apply -f https://raw.githubusercontent.com/prometheus-operator/prometheus-operator/release-0.43/example/prometheus-operator-crd/monitoring.coreos.com_thanosrulers.yaml
Closing as this appears to be answered. Please reopen if you think this is still relevant.
Most helpful comment
This issue was fixed after adding below CRDs.
Link : Helm fails to create CRDs