Why long distance pic not showing blur bkground like short distance?

I took two portrait pics with canon 50mm @f/1.8 1/60.  one is long distance shot and another one is short dist shot. Short dist shot has bkground blur and but long dist shot doesn't have blur bkground. Both pics have same DOF.

I am a new trainee and still learning. What to do get blur for long distance pic portraits.

pics are attached