According to Sky Sport Italia, Bologna rejected Nottingham Forest’s opening offer for the 24-year-old, who remains a target for Napoli.
Ndoye hasn’t formally asked to leave Bologna but has reportedly agreed on personal terms with Napoli in the hopes the two clubs can finalise a deal.
Forest are likely to go back in for the winger as they step up their pursuit of a replacement for Anthony Elanga, who joined Newcastle for £55 million earlier in the summer.
Ndoye impressed for Bologna last season as they won the Coppa Italia, scoring nine goals and providing six assists in his 41 games.