Search API problem

Hello!

I want to use Zendesk API to search users by phone number with feature searching by last numbers. But I faced a problem when call api method /api/v2/users/search with query query=phone:*ello gets response with all users in company, but I already created user with "hello" phone number. Yes, this is strange phone number with letters but I want to create universal API and if in Zendesk possible to create phone number with letters then I want to support it. I would like to note that wildcard search with * in beginning of search query correctly working with numbers. E.g. query=phone:*12 returns only user with "55512" phone number.

Vladimir.