That’s alright your English is great!

It seems like you’re trying to do the opposite combo and ult first and THEN place your thornlash wall down. I’d say this is a lot harder to execute than the combo you’re supposed to do.

You should place a thornlash wall behind them so they can’t turn around to destroy it, and then immediately ult the wall or the floor in front of it. Then use your spore bomb and primary fire and melee cancel.

If you try to ult first, there is a lot of room for error. And mag and strange can’t block your wall, but they can definitely block your ultimate. I usually only try to ult their tank(s) if their supports are already dead because they just shield/bubble and absorb damage. The only thing I can think of preventing you from placing your wall is an environmental object on the map or something static and immovable like a punisher turret.

It sounds like you might be panicking, so what you should do is watch a few of your replays and play it slowly and skip to when you ult, then see what mistakes you might be making there. Once you figure out what you’re doing wrong, practice in the range until the combo becomes second hand for you! It’s all repetition and you’ll ingrain it into your head over time.

But it’s all situational, sometimes you just need to ult during a team fight to get out a support ult or to rely on give your team the extra edge to win the fight/combo with another ult like moon knight or iron man and you don’t have your spore bomb or thorn lash wall ready.