issues with line chart

[Jemai Aymen]

Hi i'm using the LTe multicell model with voip traffic to simulate the performance of 4g lte.

i'm getting results, when i try to plot the sinr with line chart the snr over the time but starting from the max and no variation in it just like this photo 1. please i don't have the experience with omnet 6 to plot charts and i need to my final year project. i just wanna visualize snr and cqi over the time , or BELR i wanna meaning chart like photo 2 and 3.

how to do that maybe using compute or apply operations or modify something in the config chart i don't know really i need help guys.