It happened around 9 p.m. on Feb. 8 in the High Bridge section near West 164th St.
According to police, the man reportedly followed a 19-year-old woman into the elevator of an apartment building.
Police said he took the woman's phone and then punched her in the head.
The woman suffered minor injuries.
Anyone with information in regard to this incident is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477). Police say all calls are confidential.