Rowenta Focus DW 8080 oozing white stuff from sole plate

I just cleaned my iron with self-clean with no problem. Then I cleaned the sole plate with Rowenta cleaner. This is my routine, have had this iron for ??? many years.

Started ironing cotton fabric, and, after about 10 minutes, I noticed white streaks on the fabric. I found white ??? stuff on the bottom of the iron. Don't know where this came from.!! Didn't iron on anything but that cotton fabric. I do this with all my cotton fabric before working on a quilt project. So, I recleaned it, again. No noticeable “residue” came out. Sole plate had white streaks on it AGAIN.

Can you help me how to resolve this problem..???