As your node does not meet the GE requirements (Graceful Exit Guide (new procedure as of 2023-10-?)), your only option to exit the network is to simply turn off the node.
The only issue with this, is that you will not be able to reclaim the held back payments from the previous 2 months for that node. Also note that if you want to start a node later on, you will have to create a new identity as well. This would also be the case even if you do GE.