A judge will now decide if Noshad Hussain, of Regent Street, Wellington, will face a retrial early in the New Year.
The 22-year-old stood in the dock at Wolverhampton Crown Court on four counts of sexual activity with the teenage girl between September 2007 and September 2008.
He had denied all the charges.
The jury had cleared Hussain earlier in the two-week trial on a fifth count of facilitating child prostitution.
The jury was sent home by Judge Michael Challinor this afternoon after failing to reach a verdict on the other four charges, after nearly 10 hours of deliberations.
Judge Challinor ordered prosecuting counsel to submit a detailed dossier on their reasons for seeking a retrial, including whether it would be in the public interest. There will be a hearing at Wolverhampton Crown Co-urt at some point in the week beginning November 13.
Unemployed Hussain was bailed until that hearing.
The girl, who cannot be named for legal reasons, appeared in court behind a screen last week.