funnily enough, this came up as part of the discussion recently in the WSOP live stream either during the razz event or during the razz round of the 50K. steve albini was in the booth and said that there is always disagreement when it happens during events at the series because east coast and west coast rule on the error differently.
on the east coast: if one or more but less than all players are dealt 7th face up, those players with upcards on 7th keep the card, but get the option of being considered all-in (i.e., they can neither make nor call any further bets, but they are entitled to their share of the then-existing pot). play continues as normal for remaining players in the hand.
on the west coast: if one or more but less than all players are dealt 7th face up, the deal continues and all players will receive 7th face up and action will continue as normal.
there is also a provision in RROP, but i can't recall which of the above rules it follows.
OP is unclear whether some or all players have received 7th face up. if all players, i would just proceed as normal. if some players, i would determine which of the above rules you prefer and go with that from now on.