The above image was provided by Italy. It’s a multi-strip spectrogram. It’s a recording of EISCAT ionosphere heater transmissions. EISCAT exclusively uses a pulse repetition frequency (PRF) of 50 Hz. Italy’s spectrogram clearly shows a pulse repetition frequency of 50 Hz.
A solar flare doesn’t emit a pulse repetition frequency of 50 Hz. A solar flare emits a continuous barrage of electromagnetic radiation across the electromagnetic spectrum at all wavelengths, from radio waves to gamma rays.
It’s important to note the start date of recorded transmissions. Italy began recording pulse repetition frequency of 50 Hz on February 10. A day before the first reported solar flare event.