i have created backup of database in .bak file, when i was trying to restore it, it gives error

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Error window Msg-
             Restore failed for server "My-PC" (Microsoft.SqlServer.SmoExtended)
Additional Information-
       System.Data.SqlClient.SqlError:The media set has 2 media families but only 1 are provided. All Members must be provicec. (Microsoft.SqlServer.Smo)
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I am trying to restore the database on same machine and same version of sql server.
Pls help me to solve this problem.


Thanks in Advance
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