thank you,
i used magnifier and better light and:
A)circular cancel is on top of the overprint definetly
b)wavy line cancel looks like below overprint with letter C, but with number 80 and bottom of letter h and n it looks like on top.

about simple children/office printing kit

many my cancelation from chinese and korean looks like made by printing kit

I "understand" when someone create overprint and try sell it as a super rarity, but this stamp was hidden in album under few of red Washingtons.
There are few mystery questions

1) Why create overprint on canceled stamp (if it was canceled by waves)
2) Why used one american and one chinese cancelation (if it was not canceled, and if circular is realy chinese)
3) Why 80? What it can means?