According to 'Sky Sports', Leipzig increased their offer to £25m plus add-ons on Saturday for the winger, while Everton are reportedly holding out for £28m.
Rangnick remarked: "We'll see. Let's just wait another week. When you turn back time to the last day of the last transfer market, at 2pm we didn't even think about a loan of Ademola Lookman.
"It seemed impossible to get him. But four hours later we got the deal done. I said then that it wasn't a last-minute deal but a last-second deal.
"We don't plan to repeat this, because it was a very stressful situation for us. We'll just wait. When Everton wants to keep the player they will tell us. If not we'll see if there's a chance of still getting him."
Lookman impressed on a loan spell at Leipzig in the second half of last season, after scoring on his debut at the German side.