Redis [QUESTION] Use lua script to prompt moved?

I am using a lua script to implement a difference function. The specific lua code is as follows. After I execute it with spring boot, I will receive a "MOVED prompt". I don't quite understand why there is this prompt. I just created a temporary key and then used it as sdiff My environment is cluster mode

lua

local key = KEYS[1]
local keyTmp = KEYS[2]
local values = ARGV[1]

local valuesArray = {}
for value in values:gmatch("[^,]+") do
    table.insert(valuesArray, value)
end


local ok, result = pcall(function()

    redis.call('SADD', keyTmp, unpack(valuesArray))

    local res = redis.call('SDIFF', keyTmp, key)

    redis.call('DEL', keyTmp)
    return {200, "success", res}
end)

if not ok then

    return {401, result,{}}
end

return result

Comment From: sundb

you should make sure that KEY[1] and KEY[2] are all belong to the current cluster node, otherwise it will return the MOVE prompt.