I don't think they will fix it..as this issue I'm already reported a while ago...even my post not get reply and other people report not get reply too..stay previous rom with no bug download big apps from PS..or this not get fix in future might reinstall back original rom ..
Facing install issues on Mi 6 using 10.3 stable.
Same issue on data or Wi-Fi. Download will hang at the end. If download is complete, killing Play Store and rerunning will continue the install.