MATLAB: My domain is blocked by CORS policy: No ‘Access-Co​ntrol-Allo​w-Origin’ header is present on the requested resource.

cors access-control-allow-originThingSpeak

Since this week I cannot add a talkback command using Javascript/Ajax. I get the following error in my web browser (Chrome)
Access to XMLHttpRequest at 'https://api.thingspeak.com/talkbacks/32490/commands.json?apikey=xxxxxxxxxxxxxxx&command_string=OFF&position=1' 
from origin 'https://desmon.fr' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.
However the same code was working perfectly 2 weeks ago. It seems that my website is blocked on ThingSpeak.
When I try to submit the same command using CUIRL it works (from my PC).
curl -X POST https://api.thingspeak.com/talkbacks/32490/commands.json?api_key=xxxxxxxxxxxxxxxxxx -d "command_string=ON&position=1"
Here is the Javascript code I use:
$.ajax({	
    type: 'POST',
    url: 'https://api.thingspeak.com/talkbacks/32490/commands.json?apikey=xxxxxxxxxxxxxxxxxxxxxxx&command_string='+newState+'&position=1', 
    crossDomain : true,
    success: function(data) {

Best Answer

On further investigation, it appears that there is a difference between your AJAX code and the CURL command:
AJAX request is: 
https://api.thingspeak.com/talkbacks/32490/commands.json?apikey=xxxxxxxxxxxxxxx&command_string=OFF&position=1
CURL request is 
https://api.thingspeak.com/talkbacks/32490/commands.json?api_key=xxxxxxxxxxxxxxxxxx -d "command_string=ON&position=1
Note the difference "apikey" v/s "api_key".
Can you please modify your AJAX request to use api_key and try again?
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