Unable to get data after adding custom filter variable

Hello ,

I have added a filter to filter by firmware version , I have written following query

|> filter(fn: (r) => r[“_measurement”] == “Infra” or r[“_measurement”] == “AppMon”)
|> filter(fn: (r) => r[“_field”] == “MUtil” or r[“_field”] == “Firmware_Version”)
|> filter(fn: (r) => contains(value: r[“region”], set: ${Region:json}))
|> filter(fn: (r) => contains(value: r[“Firmware_Version”], set: ${FW_Version:json})

But getting this error
image

The Firmware_Version is a field in Infra measurement , as you can see there is already a filter for region which is working fine but when I tried to add for Firmware Version ,it isnt working and getting error ,Please help ,Thanks.

Note:Lines in bold are added by me , if we remove that the query is working fine

grafana version 8.2.6