The COMMIT TRANSACTION request has no corresponding BEGIN TRANSACTION.

[cmrhema]

Hello
I am using Asp.net with VC# having backend SQL SERVER
I have written a procedure in sqlserver as below.
It does not throw any error in sqlserver.

This is the procedure

set ANSI_NULLS ON
set QUOTED_IDENTIFIER ON
GO
ALTER procedure [dbo].[updatecommand]
as
declare @speed int
declare @ignition int
declare @basestationname varchar(50)
declare @registrationno varchar(50)
declare @exp int 
set @exp=null
 
begin
declare opencur cursor for 
select registrationno,speed,ignition,basestationname from gpsdata where datediff(mi,gps_datetime,getdate())>10 order by gps_datetime
end
 
open opencur
 
fetch next from opencur into @registrationno,@speed,@ignition,@basestationname
WHILE (@@FETCH_STATUS = 0)
begin
if(@speed<>0 or @ignition<>0 or @basestationname<>null)
begin Tran 
    update gpsdata set speed=0,ignition=0,basestationname=null where registrationno=@registrationno
    set @exp=@@error
    if (@exp<>null)
        rollback Tran
    else
    begin
        update gpsdata_history set speed=0,ignition=0,basestationname=null where registrationno=@registrationno
        set @exp=@@error
        if(@exp<>null)
             rollback Tran
 
    end
 
fetch next from opencur into @registrationno,@speed,@ignition,@basestationname
 
            commit Tran
 
end
close opencur
deallocate opencur

But when i execute the above procedure in asp.net i get the error
Commit Transaction has no corresponding Begin Tranasaction

This is code for asp.net

MyCon.Open();      
        SqlCommand MyCmd = new SqlCommand("updatecommand", MyCon);
        MyCmd.CommandType = CommandType.StoredProcedure;
        MyCmd.ExecuteNonQuery();
        MyCon.Close();

Kindly help
Regards
cmrhema