Loki unexpected error. TypeError: Cannot read property 'slice' of null

I have 3 servers. 2 linux and one windows.
I installed Grafana 7.0.3 and loki 1.6 on both the linux servers and grafana 7.0.3 on the windows server.

My issue is that on the windows server when i do a explore in loki it works, i can do a query. But when i want to see it live it gives the following error.

An unexpected error happened

An unexpected error happened

TypeError: Cannot read property ‘slice’ of null
in t in WithTheme(undefined) in u in div in div in Collapse in t in t in p in t in x in t in t in main in div in t in div in div in t in WithTheme(undefined) in x in t in t in div in div in div in t in t in div in t in x in r in Unknown in t in Unknown in h in Unknown in Unknown in t in t in l

I don’t have this issue on the 2 linux servers.

What can i do to make it work?

I’m experiencing the same issue. I have 2 monolithic server instances behind nginx proxy. I can view live tail while grafana datasource is the single loki instance instead of proxying through nginx. But when I change datasource to nginx, It shows the error you mentioned.