There are not currently any low-cost airline routes between Ibiza and Paris (Charles de Gaulle) with Vueling.
Instead you could try browsing budget flights between Ibiza and Paris (Charles de Gaulle) with all airlines.
Another option would be to try browsing all low-cost airline routes to Paris (Charles de Gaulle) or all budget routes from Ibiza.
In the meantime, this error has been logged.