You can find some tutorials on YouTube
https://www.youtube.com/watch?v=CCUrQcn8pE4

Some say to use tooth paste to clean it !

Happens to me all the time.
Mix 3 parts baking soda, and 1 part water, together to form a paste. Apply this on the blackened area of your iron and leave it on for some time. Don’t let the paste get into the iron’s steam holes, just the surface which gets heated. Now wipe it off clean; the majority of the stain should come off.

It doesnt sound good considering the little use of it,l would take it back!

Double check the how to use booklet, see if you’re doing something wrong or maybe not doing something you should be doing. If tights all good, call the store you bought it from for a refund or replacement as it shouldn’t be looking like that after such a short time

Yes for sure I would check with the manufacturer as well!

refund, replace, i know they need cleaning but i have used my other brand-name iron, a few times and it is not dirty or burnt.

the booklet should say how to clean it, but I would take it back to the shop you purchased it from, as it should still be under warranty

I would check with the manufacturer what is the best method to clean the plate, anything harsh will damage it further. A good idea to empty the water out too!

I would return it straight away as you have only used it 3 times,also l burnt a top by having the iron too hot and it left black marks and was told to rub lemon on it and it worked and removed the black marks.

I use a hot iron cleaner, the iron needs to be hot and then put this gel stuff and iron it off on an old tea towel. I heard sprays like fabulon cause the blackness

Take it back to the place of purchase, this happened to me once and i was given a new replacement iron. If they dont refund item contact tefal and tell them what happened they will most likely replace it. ( hope you still have the reciept)