Cluster not ready....

Hello,

I have 3 Roots which are working as a Cluster.
I have changed on every Root the IPs of those.

Since this change, I cant do anything.... only stop and start of the VM´s are possible.

I can only see one of the 3 Nodes that is online. The other two are offline... Before changing the IP this problem wasn´t.
When I want to start a VM on Node1, I must login into the Interface of Node1... If I want to start a VM on Node2, I must login on Node2 and so on....

When I want to change a VM the Message is:
unable to open file '/etc/pve/nodes/NODE2/qemu-server/103.conf.tmp.509579' - Permission denied (500)

When I want to add a new VM the Message is:
cluster not ready - no quorum? (500)

What can I do ?

I hope someone can help me :)

Thank you