Can we see the picture of the slab and label? If it's a S/S then it's a variety and not an error. When a person sends a coin to be attributed they have to state it on the form. PCGS will not attribute if not mentioned. So they made no mistake.
PCGS will probably put it on the label if you wish to pay for it. You have to ask and pay extra. Not worth the cost on this coin.
yea i got a 1908 s indiaN HEAD WITHOUT THE MENTION OF THE S MINT MARK FROM PCGS.. I GOT IT FOR A 1908 REG CENT COST
Now that's an error on PCGS's part. If it had a mint mark and was not mentioned on the label, that's a big mistake. The mistake was also on the person who sold you the Indian Head Cent for not noticing the S on the back. Good catch by you and way to make a nice score.