What to do?

What markete situation is going of 2bed d/d in gulshan iqbal block 4 karachi nowadays? I want to sale my flat in sb project with lift but here the agents r continuously discouraging me that its worth not more than 40-42 although its not a very old project and all other projects around it have demand of 55 for 2 bed d/d and i want to sale it in 45-47. Kindly tell me the actual price here and what should i do?