Both nodes have Role=<none> ; How to assign master role to a node

Hi *.
I’ve setup a two node cluster with microk8s and it works. I ran in an issue with an error message like

1 node(s) didn't match Pod's node affinity/selector.

After some troubleshooting I found out that none of my nodes seem to have the master role

kubectl get nodes -o wide
NAME                STATUS   ROLES    AGE   VERSION                    INTERNAL-IP     EXTERNAL-IP   OS-IMAGE             KERNEL-VERSION     CONTAINER-RUNTIME
ubuntu-k8-sradtke   Ready   <none>   14d   v1.23.3-2+d441060727c463   10.220.151.51   <none>        Ubuntu 20.04.3 LTS   5.4.0-99-generic   containerd://1.5.7
k8worker1           Ready    <none>   11d   v1.23.3-2+d441060727c463   10.220.150.90   <none>        Ubuntu 20.04.3 LTS   5.4.0-97-generic   containerd://1.5.7

Also “kubectl descibe node” shows the role of the supposed master node as role=none:

kubectl describe node ubuntu-k8-sradtke 
Name:               ubuntu-k8-sradtke
**Roles:              <none>**
Labels:             beta.kubernetes.io/arch=amd64
                    beta.kubernetes.io/os=linux
                    kubernetes.io/arch=amd64
                    kubernetes.io/hostname=ubuntu-k8-sradtke
                    kubernetes.io/os=linux
                    microk8s.io/cluster=true
                    node.kubernetes.io/microk8s-controlplane=microk8s-controlplane
Annotations:        node.alpha.kubernetes.io/ttl: 0
                    projectcalico.org/IPv4Address: 10.220.151.51/16
                    projectcalico.org/IPv4VXLANTunnelAddr: 10.1.86.64
                    volumes.kubernetes.io/controller-managed-attach-detach: true
CreationTimestamp:  Sun, 30 Jan 2022 13:41:26 +0000
Taints:             <none>

I think it worked in the beginning (not sure though) but I rebooted the master node once.
Any idea how I can assign the master role to the relevant node in a microk8s cluster?