[1] Born in 2000 in Seriate in the province of Bergamo, she began playing football in kindergarten, starting competitive activity at 13–14 years old with San Leone and then also playing 7-a-side football in regional CSI championships.
[2] After finishing the season in 5th place in the standings, the following season she became a starter and won Group B of Serie B with a 3-point advantage over Inter Milano, thus accessing the play-off for promotion to Serie A against Pro San Bonifacio, winner of Group C, and winning it 5–4 on penalties after a 1–1 draw in regulation and extra time.
She made her debut in the top division on 22 September 2018, in the 1st match of the championship, on the Tavagnacco pitch, losing 1–0.
After playing for the entire beginning of her career in Orobica, in the summer of 2020 she moved away from home for the first time, going on loan to the Tuscan club Florentia.
Lonni was called up to the Italian youth teams of the Azzurri, but did not play in official matches.