I've spent several hours on hold and talked to someone *** minutes ago who said she'd c...

I've spent several hours on hold and talked to someone *** minutes ago who said she'd call me back immediately at my cell phone number (* *** ***-****) and haven't heard back. I'd additionally confirmed with Iceland Air that this request is possible, but the airline can't because I booked via JustFly, they said only they can make the change.**I am calling about my booking for ***-***-*** (Confirmation Iceland Air NGKP*N).**My June **th flight from Cleveland to Helsinki is okay, no changes there.**However, the airline made a change to my return flight on July **th from what I originally had purchased-- my return to the US slipped back an hour in Boston and that interferes with other travel plans. So, if possible I was hoping to change my final destination for the July **th flight to Cleveland (and not Boston.)**If we changed from Iceland Air Flight *** (KEF -* BOS) to Iceland Air Flight *** (KEF -* CLE), I'd be very happy, they're within the same hour departing Iceland. Looks like an easy switch, same airline, almost same time, seats are also available.**Please advise on what we can do. The agent I spoke to was very nice, but it's been over ** minutes and she hasn't called me back. I made sure we repeated the phone number (and had also given it to the original rep who was assisting me too.)