Problem with search by fields with cyrillic characters on self-hosted version

Hellow,

In the self-hosted version (v1.5.0 installed using Cloudon), the search for fields with Cyrillic characters is case-sensitive (both in the program and via the API). The search for fields with Latin characters works correctly (it is not case-sensitive).

At the same time, in the SaaS version, the search for fields with Cyrillic characters works correctly (it is not case-sensitive)

What could be the problem?