我個美國簽證，喺日本買嘢時，俾店員釘咗個退稅紙喺上面，而家有兩個釘口，仲有冇效，好擔心過唔到美國關?

Thanks for your advice

It should not be a problem.

In the past, the U.S. CBP had the same practice that stapled I-94 to the passport.

冇問題，呢個係習慣，美國入境只睇簽證，同埋你係咪恐怖分子