Diablo II LoD steam deck install issues

Hello! I installed Diablo II (1.14b), but I can’t install LoD as it asks to install Diablo II. I used my Nickname and CD keys, downloaded installer launcher from blizzard website. I manage to open game and play, but can’t install LoD, which troubleshooting could you recommend to me, please? I use Steam Deck and proton.