u need to include the data you want to send as the third argument to the fetchRemote, also the method should be in string
local apiKey = "..."
local forumAddress = "..."
function testing(orderID, content)
local sendOptions = {
connectionAttempts = 5,
connectTimeout = 7000,
method = "POST",
headers = {
["Content-Type"] = "application/json",
},
}
local postData = toJSON({
status = "completed",
})
fetchRemote(forumAddress.."/wp-json/wc/v3/orders/"..orderID.."?key="..apiKey, sendOptions, function(responseData, error)
if error == 0 then
outputChatBox("success" .. responseData)
else
outputChatBox("failed, " .. error)
end
end, postData)
end