You possibly encounter a bug

In fact when you get CRASH, it was probably set at your level (or one level below).
Normally, you shouldn't be able to upgrade it higher than your level. But with some weapons (I guess CRASH is one of them), you can upgrading them at maximum even if you're not max level (i.e level 50).
It's an issue because you don't really know at which level these weapons are. But anyway, when they reach the level 50, they disappear from the upgrading tab. At the end, you don't really "waste" components. Maybe better, you get a weapons with stats higher than you should be able to have normally.
In short, at level 29, you should be able to upgrade your CRASH to the level 50 and still be able to use it.