https://www.youtube.com/watch?v=xl0jzHsLL9M
https://www.howtomendit.com/answers.php?id=22998
http://www.fixya.com/support/t11300896-tefal_pro_express_turbo_leaking_when
Basically, if you do a Google search for "Tefal express leak" [ making sure you get the make right :-) ] , you'll see this is a very cpommon problem with Tefal steam generator irons.
My thought would be to try a few of the descaling suggestions but plan to cut your losses, do some research and buy one with a better reputation.
Acp, August 2017