People didn’t accept my gift

As far as I know, you can ask support to add a few GA slots if you were so stupid (just like me many years ago) to lose them all.

Yeah, that's an impressive number of unaccepted gifts.

I'm more impressed by the fact that not a single one of the winners bothered clarifying the issue within the giveaway, as per the usual expectations winners are held to. Unless the OP is deliberately blacklisting them and just being an all-around troll, I'd say the responsability primarily'd lie on the winners by this point regardless of whether or not Ro4I is making an error in the process along the way.

Then again, I can't really say that, given that both the current FAQ and Guidelines seem to completely skip over that expectation, instead (as far as I can see) exclusively recommending contacting the GA creator on Steam (which, y'know, is usually not recommended as anything other than an absolute last resort, if the GA creator themself didn't solicit such?)

In short, I think this one might be on cg. :S

Guidelines: Allow the giveaway creator one week to send the gift. Please be patient and do not contact them during this time. If the gift is not received after one week, you may contact the giveaway creator on Steam to follow-up.

FAQ: If the gift is not received after one week, you can mark the gift as not received, and attempt to contact the giveaway creator on Steam to follow-up.

While the rules seem to completely pass over it now, it's a pretty well established thing that winners have an obligation to clarify any issues [either within the giveaway or, if blacklisted, directly to support], just as GA creators have an obligation to clarify that they've attempted to send the gift. The site just doesn't work very well if there's doubt or confusion on either end of that process. Or, to rephrase that, if the winners don't clarify that there is a problem, support can't reasonably accept that there is one, not anymore than support can accept that an attempt to send a gift was made if there's no indication at all that it was.

End result of that all being, if the GA creator presents evidence of their attempt to send the gift- either before that initial week period, or just after a week period presently- it'll overrride the Not Received in terms of justifying a reroll/deletion, if the issue can't be determined. That said, all of the six winners appear to have been online recently, so it's unlikely it'll cause any awkward results for this particular circumstance, assuming the initial fault was in fact on the OP. It's still good practice for winners to be attentive to reporting such matters in a timely fashion, however.

tl;dr version: Six winners, six failures to provide proper feedback; Is that like playing Russian Roulette with a revolver where every chamber was loaded?