How to migrate *.sqlite database via FMDBMigrationManager?

I'm using FMDB IOS framework to manage my sqlite database.

But now I have second version of my database, so I need to update my sqlite file (on devices with installed app)

Here is my steps: (database is in Application Support/db/db.sqlite )

1. create second . sqlite file (named "2_db.sqlite") and copy it into my main Bundle


2. 
   

   Use this code on every start

   
   

   
   -(void)migrateWithDBAtPath:(NSString *)dbPath {
       FMDBMigrationManager *manager = [FMDBMigrationManager managerWithDatabaseAtPath:dbPath migrationsBundle:[NSBundle mainBundle]];
       NSError *error = nil;
       BOOL success = [manager migrateDatabaseToVersion:UINT64_MAX progress:nil error:&error];
   }
   
   

dbPath is .../Library/Application Support/db/db.sqlite

But after this steps I have no migration and 0 pendingVersions in migrateDatabaseToVersion:progress:error:

What am I doing wrong? Thanks.