Volume 2 Chapter 6 was serialized in the June issue of Gateau magazine, it usually takes about a month or 2 before a chapter goes to single edition on sites like cmoa and renta but the magazine usually has a digital copy you can buy (idk specifically about Gateau but 花音 magazines digital version is on Comic fuze). The author recently wrapped up stuff to do with the CD drama so I'm sure more regular serialization will start by the end of the year beginning of next year.
I double checked it was actually the August issue (I bought a used copy on mercari jp cuz it was sold out on animate) the digital became available on June 30th https://renta.papy.co.jp/renta/sc/frm/item/409158/title/2850196
anyone know when vol 2 is coming out :3