i suggest you search for a monitor instead with this code line 264 - 269

-- Monitor init
local function findMonitor()
  for _, name in ipairs(peripheral.getNames()) do
    if peripheral.getType(name) == "monitor" then
      return peripheral.wrap(name), name
    end
  end
  return nil, nil
end

local mon, monitorName = findMonitor()

if not mon then
  print("Error: No monitor found")
  return
end

if mon.setTextScale then
  mon.setTextScale(1)
end

it will also error out if no moniter is found