ActionView::Template::Error (TinyTds::Error: adaptive server connection timed out

Question

enter image description here

above error getting on production. it's working on staging env.

in database.yml given below configuration

 pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
 timeout: 4000000

also for each loop i have used

(2..spreadsheet.last_row).each_slice(500) do | batch |
  batch.each do | i |
   # remaining code here
  end
 end

but after using above still getting same error on production env.