Two month baby nose is blocked ?

Hi . My two month baby not feeling well her nose is blocked past 3 weeks now she start vomiting also not able to sleep properly I try everything . Steam ' flo baby saline ' trying to clean her nose wid baby nasal spray 'baby panadol but nothing working we went to 3 doctors n they said we r already trying wat ever is there can't give any thing else . We have a long flight after two days if any one know some good syrup for cold n flu or any thing else to relax her that would be a great help thanks