Deploying consul on existing kubernetes cluster in GKE

Question

I am trying to deploy Consul service mesh to an existing kubernetes cluster running on GKE. The cluster already has workloads running in production.

For this matter i followed the following guide

https://learn.hashicorp.com/tutorials/consul/service-mesh-deploy

This is without TLS, ACL etc, as I didn't want it to be intrusive to the cluster to start of with and I could enable it later. So after a successful deployment I wanted to enable ACL, too this end I ran the following helm command.

helm upgrade consul hashicorp/consul --namespace consul --set global.acls.manageSystemACLs=true

After this was done, most of the existing deployments / workloads seemed to be down, and the fix was to uninstall Consul again.

So now I am left wondering what went wrong, is something wrong with my method of installing Consul on the cluster or is it something else?

Help is greatly appreciated

EDIT Add yaml file

global:
  name: consul
  datacenter: dc1
  metrics:
    enabled: true
    enableAgentMetrics: true
server:
  replicas: 1
  resources:
    requests:
      memory: "200Mi"
      cpu: "100m"
    limits:
      memory: "1Gi"
      cpu: "1"
client:
  resources:
    requests:
      memory: "200Mi"
      cpu: "100m"
    limits:
      memory: "1Gi"
      cpu: "1"
ui:
  enabled: true
  service:
    type: LoadBalancer
connectInject:
  enabled: true
  default: true
controller:
  enabled: true