YPPH/21 AMANA5 AMANA Y31 LAKIR Y69 LEO DCT WBR DCT SCHEE DCT YTGT/TG2EG.R29

Recommended optimum of FL330. Last weekend I got the flight going and walked away for a bit after 20 minutes. I came back 20 minutes later to find the plane upside down on the ground. I did the same flight attempt again this morning and it happened again. It appears that at or after waypoint YOKRA, not long after reaching FL330, the plane veered off to the left and crashed.

I tried the flight a second time this morning, this time sitting at PC and monitoring to that same exact location. After a short period at FL330, the plane struggled for speed, almost stalling, and auto thrust kicked into TOGA with no help. I disconnected A/P and ATS but it continued to do the same thing once connected again. I had to descend to FL310 for stability. Is this something wrong with the plane or the inability to fly at that cruise flight level even though it says optimum was FL330?

I have done other flights at FL330 with no issues, although this route has an extra 2 or 3 tons to fuel. If that is the case, I would expect the optimum flight level to be below FL330.

Any ideas? Thanks.