stalling/no power

What is your question?

I have had this car fixed 2 times for this same problem. It actually stalled when I was driving it the first 2 times and would not restart. This time, it will stall if I am not continually going at least 20 miles a hour. Then, if I have to come to a complete stop, it stalls out. At least this time I can restart it, but I concerned that one time it will not restart. Does anyone know a trusted mechanic that can help me fix this problem once and for all? Thank you,