Lines appearing in the frequency/time graph

[Hamzu24]

Weird lines are appearing in my graph of CSI data frequency over time? Either horizontal or vertical. Here are two examples:

Would anybody know what's going on here, or how to fix it? I can implement a filter for constant frequencies but am worried its a symptom of a deeper issue that needs addressing.

Thank you!

[zeroby0]

Doesn't look like real proper CSI data. Which device, how was the graph created, and are you using a packet filter? Some packets are not OFDM and will not have real CSI.