Same happens with my TV LG OLED C2 (2022 model) 55 inch which supports Dolby Vision and Dolby Atmos/Dolby Digital . I am able to use Dolby Atmos on all OTT apps like Netflix, Amazon Prime on LG web OS except Disney+Hotstar. Hotstar alone plays in Stereo. There may be the issue in WebOS of LG for LG C2 Disney+HS