I think you should look at your for each loop, this is running for each file, so if you have 3 files it's running 3 times.

I think you should look at your loop...

1 file:

everything is ok

2 files:

1 is ok

1 failes

1 is ok

1 failes

3 files:

1 is ok

2 failes

1 is ok

2 failes

1 is ok

2 failes

I think you...

I think you should convert the date+time from the source to a date instead of adding time to the parameters:

SELECT ModifiedDate

FROM ...