Dua changing taqdeer

Mufti sir, Aoa, may Allah (S.W.T) bless you in abundance for the noble work ameen. Sir, can taqdeer be changed by dua? a proposal which was close to acceptance was refused by the mother because istikhara wasnt clear. I am really like the family and despite other proposals that came, i want more than ever for the family to call again with decision in my favor. i have been trying one of the methods of the ‘tried and tested methods to get pious poposals’. i want to ask if dua can at all change taqdeer and that too in one’s favor. please tell me complete dua to change the course. Also, if provided certain information can you tell if any possibity of marraige exists and will it be better for me. JazakAllah, waiting anxiously for your kind reply.