Acts 16:13 And on the Sabbath day we went out of the city to the riverside, where prayer was customarily made; and we sat down and spoke to the women who met there. Its seems that pray always works on God’s timetable. We have our schedule, and God has His schedule. In this verse in Acts, prayer had been going on some time, look at the phrase “where prayer was customarily made“.
At the God moment, the God time, God acts and prayer is answered. Trying to change God’s clock does not seem to work. Just waiting for God does work.