All the settings were set properly, i even crossed checked if the less secured apps(setting) was turned ON, it was ON.
But the catch was
As soon as i generated a app password and used the same in the mail.properties VOILA
its done. Now i am receiving the emailā¦ 
We can copy the auth token right from the Blynk app, but i wanted to know what was going wrong, now i learnt something new. Thank you so much for solutionā¦ 