The transfer saga had been thrown into disarray after Corinthians refuted claims from City that a deal had been agreed for the homesick Argentine striker's return to South America.
But speaking after City had claimed 2-1 victory over Vancouver Whitecaps, Mancini remains confident a deal could be struck in the next few days.
"I slept last night and I had a game to prepare for today so I don't know any more," he said.
"The clubs are talking. I haven't spoken to it. They only have one number and it does not work at the moment."