After upgrading to 15.0.5 from 14.10.5 Artifacts missing

Hello everyone,
Yesterday I decided to update the Gitlab build along the following path: 14.7.0ee - > 14.7.0ce - > 14.9.5ce - > 15.0.5ce. Everything went well, but after upgrading to 15.0.5, build artifacts was missing (see below) and the storage value in project is strange (below zero).

So, what should I check and how can I restore artifacts staying with 15.0.5? Please, help.

Before (14.9.5ce):

After (15.0.5ce), the storage value in project is strange, below zero:

Downgrade from 14.7.0ee - > 14.7.0ce performed according to the page Downgrading from EE to CE | GitLab