Hello,

In https://www.sqlite.org/src/file?ci=trunk&name=ext/jni/src/org/sqlite/jni/capi/CApi.java&ln=201-212

  private static native sqlite3_backup sqlite3_backup_init(
    @NotNull long ptrToDbDest, @NotNull String destTableName,
    @NotNull long ptrToDbSrc, @NotNull String srcTableName
  );

  public static sqlite3_backup sqlite3_backup_init(
    @NotNull sqlite3 dbDest, @NotNull String destTableName,
    @NotNull sqlite3 dbSrc, @NotNull String srcTableName
  ){
    return sqlite3_backup_init( dbDest.getNativePointer(), destTableName,
                                dbSrc.getNativePointer(), srcTableName );
  }

parameters should be *DbName / *SchemaName and not *TableName

Regards.