I am doing FMR frequency variation by sweeping the magnetic field using a thin film, but the FMR spectra show multiple peaks merged in a single peak.

1. do I have to take the linewidth and resonance field value for two different peaks

or

2. do I have to consider it as a single peak and take the "dH" and "H_res" values for the extreme maxima and minima

Can somebody please suggest the method to calculate FMR linewidth and resonance field value using such spectra. any reference, link, or explanation would be a great help

i am attaching the JPG image of the FMR spectra i am getting