Gitlab ce kubernetes integration -- Something went wrong while installing Helm Tiller

Hallo all

We have at our company gitlab-ce in use.
On a virtual machine with debian 9 and gitlab 12.10.0
All works ok with gitlab.

I have attempted to integrate two seperate kubernetes clusters, one with 1.14 and the newer one with
1.18.5.

I can get all the details needed to connect to the cluster but when I want to do the next first step and install Helm it fails on both.

I see very little I can debug. and little in the gitlab logs.
{“severity”:“INFO”,“time”:“2020-07-14T13:53:53.623Z”,“correlation_id”:“nfFiifW6Pj8”,“service”:“Clusters::Applications::InstallService”,“app_id”:3,“app_name”:“helm”,“project_ids”:,“group_ids”:,“event”:“begin_install”}

but under gitlab -> kubernetes -> Applications. It continues to show
"Something went wrong while installing Helm Tiller " " Failed to install. "

How can I see what might be causing this? And of course importantly how can I get to integrate my cluster with my gitlab ?

I have tried with both. I have added and removed multiple times.
On a test machine I had another gitlab with latest version 13.1.4 but the same issue.

I have only seen one or two issues with HTTP Proxy but this seems to be correct.

If anyone has any idea I would really appreciate it. Integrating the two would really help our developers to deploy to the cluster.

Thanks
Julian