Yeah. That wasn't a good idea. Anytime you send a gift card or cash, bring it to the Post Office and pay a bit more to obtain a tracking number. The card may be caught in the bottom of a mail bag; it may still get there.
I send anything of value like birthday cards with gifts in them priority mail two-day delivery. I drop off the package at the post office and the receipt has a tracking number and they also notify you when the package has been delivered.
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