rednet door client and server

i need help with a door client and server. i am using the mag strip cards from immibis peripherals

code

masterId = 3
reader = peripheral.wrap("left")

rednet.open("back")

while true do
  event, data, side = os.pullEvent("mag_swipe")
  rednet.send(3,data,143)
  sId, msg, dist = rednet.receive("143")
  term.setCursorPos(1,1)
  if data == msg then
		  redstone.setOutput("right",true)
		  sleep(5)
		  redstone.setOutput("right",false)
  end
end

Hey, rick3333 - I'll start with the standard suggestions:

1. Please use code tags [.CODE] [./CODE] (without the dots) so your code is easier to read.
2. Please tell us what you expect the program to do, and what the program is actually doing.
3. Please include the full text of any error messages.

I've put your code in code tags and indented it below so it's easier to read, and I think I see one error right off the bat.

masterId = 3
reader = peripheral.wrap("left")

rednet.open("back")

while true do
  event, data, side = os.pullEvent("mag_swipe")
  rednet.send(3,data,143)
  sId, msg, dist = rednet.receive("143")
  term.setCursorPos(1,1)
  if data == msg then
    redstone.setOutput("right",true)
    sleep(5)
    redstone.setOutput("right",false)
  end
end

You aren't specifying your protocol with a string.

Change…

rednet.send(3,data,143)

to…

rednet.send(3,data,"143")

It looks like you're sending the number 143 instead of a string.

rednet.send(3,data,143)
--#probably should be
rednet.send(3,data,"143")

EDIT: :ph34r:/> 'd