basically, I have setup spk, dkim and dmarc for mail authentication. For this, I used this tuto. All worked correctly and I got this result:
Now to confirm everything is working correctly, I have tried, on and another site (here), But seems like dkim does not work. I am new in this technology. I have read about dkim, spf, dmarc. But I have not practical experiment with it.
Why are these site giving a different result? I am new in this technology I want to know Where I should start to solve this?
thanks in advance.