Hi @Yana_Syritskaya,
Thanks for your interest in SQLCipher and for posting to the discussion forum.
This warning/error typically means that you’re not properly importing SQLCipher’s variant of the sqlite3.h. How are you integrating SQLCipher? Are you following the instructions on this page: SQLCipher Community Edition - iOS and macOS Tutorial - Zetetic if you’re using Community Edition? or these instructions SQLCipher for iOS and Mac Catalyst - Zetetic if you’re using Commercial Edition?
It could also be that you have a separate dependency which transitively include/links standard SQLite. This post is example of that: Cannot open encrypted database with SQLCipher 4 - #4 by mmoore
If you’re using SQLCipher Commercial edition, feel free to reach out to us at support@zetetic.net for private prioritized support.