I’m having the same problem with my brand new X1C:
I’m about to visit my dealer and probably return the printer. It’s not what sponsored reviews say about X1C. I’m having serious problems with stringing, even with dried Bambu Lab filaments. There are many other bugs and glitches as well (Bambu Studio, printer FW, Bambu Handy). It seems Bambu engineers don’t fix bugs.
P.S. Ironing is not what I’m looking for.