Can someone please help me with below issue that I am facing?

Hi Everyone, Can someone please help me with below issue that I am facing? So in my plpgsql function I have declared a variable start_time of type timestamp with time zone and assigned the value as now(). Then before the return statement of the function i am inserting this data into one more table with the start time as the start_time variable and end_time as now() The function took around 2min and it also entered the time data into this table but the problem is that the start time and end time is the same even though I have initialised the variable in the beginning of the function.. I was expecting 2min delay in the start time and end time.. Can someone please let me know what am I doing wrong?