Creating grafana filter variables from influxdb 2.7.4 version _fields return no data


I am using Grafana 10 and influxdb 2.7.4.

I am running below code to form a table.
There are 11 filter variables on grafana as you can see in below code.
When i define all 1 variables as tags in db it is showing all data.
But if i define one of the as field i get no_data.
For example if i define SiteNameX variable corresponding influxdb column Site_Name as a field i cannot get any data. How can i define influxdb fields as variables in Grafana.
Because i dont want to use so many tags, because it increase number of series that sometimes cause max series error in Grafana. Because i have very big data sometimes a table panel in grafana is 700.000+ rows. So is it possible to create Site_Name in influxdb as a field and use it as a variable in grafana.

from(bucket: "VFBckStrg")
  |> range(start: -30d)
  |> filter(fn: (r) => r["_measurement"] == "VMwareRawData29")  
  |> filter(fn: (r) => r["Client_Name"] =~ /^${ClientNameX:regex}$/)
  |> filter(fn: (r) => r["Schedule_Type"] =~ /^${ScheduleTypeX:regex}$/)
  |> filter(fn: (r) => r["Policy_Name"] =~ /^${PolicyNameX:regex}$/)
  |> filter(fn: (r) => r["Site_Name"] =~ /^${SiteNameX:regex}$/)
  |> filter(fn: (r) => r["Policy_Type"] =~ /^${PolicyTypeX:regex}$/)
  |> filter(fn: (r) => r["Owner_Group"] =~ /^${OwnerGroupX:regex}$/)
  |> filter(fn: (r) => r["Group_Manager"] =~ /^${GroupManagerX:regex}$/)
  |> filter(fn: (r) => r["Senior_Manager"] =~ /^${SeniorManagerX:regex}$/)
  |> filter(fn: (r) => r["Job_Status"] =~ /^${JobStatusX:regex}$/)
  |> filter(fn: (r) => r["Service_Name"] =~ /^${ServiceNameX:regex}$/)
  |> filter(fn: (r) => r["Master_Server_Name"] =~ /^${MasterServerNameX:regex}$/)
  |> pivot(rowKey:["_time"], columnKey: ["_field"], valueColumn: "_value")
  |> keep(columns: ["_time", "Start_Time", "Client_Name", "Policy_Name", "Policy_Type", "End_Time", "Service_Name", "Owner_Group", "Senior_Manager", "Group_Manager", "Schedule_Type", "Site_Name", "Job_Status", "Master_Server_Name", "Schedule_Type", "Job_Status", "Job_Status_Code", "Duration_Minutes", "Written_Size_MB", "Real_Size_MB", "throughput_MB_per_sec"])