When entering information in the sqlite database, I encounter the following error (image).
What is the solution to fix this error?

  static Future _onCreate(Database db, int version) async {
    await db.execute("CREATE TABLE users(id INTEGER PRIMARY KEY AUTOINCREMENT,groupId INTEGER ,name TEXT)");
    await db.execute("CREATE TABLE costs(id INTEGER PRIMARY KEY AUTOINCREMENT,title TEXT,price INTEGER,groupId INTEGER,partners TEXT,buyer TEXT,FOREIGN KEY(buyer) REFERENCES users(name))");
  }