Checklist

• I am sure the error is coming from Pyrogram's code and not elsewhere.
• I have searched in the issue tracker for similar bug reports, including closed ones.
• I ran pip3 install -U https://github.com/pyrogram/pyrogram/archive/master.zip and reproduced the issue using the latest development version.

Description

When i use Client.iter_history(offset_date=, reverse=True) it returns all history without offset_date limits. I.e. I get messages created before offset_date and after offset_date.
This is undocumented here behavior?
Or this its a bug?

Would be good to fix this behavior to get messages older that date in reverse order.
And better for me, if it possible, to get messages newest that date in reverse order, as i feature requested in 495
Thank you.

Steps to Reproduce

offset = int(datetime(year=2020, month=9, day=14, hour=4).timestamp())
    for m in app.iter_history('me', offset_date=offset, reverse=True):
        print(datetime.fromtimestamp(m.date).strftime('%Y%m%d/%H:%M:%S'), m.message_id)

My out:

20200912/04:36:41 53361
20200912/04:36:48 53362
20200912/21:36:49 53387
20200914/03:05:36 53510
20200920/12:56:04 54064
20200921/02:09:35 54074

Without offset_date and reverse=True output the same but reversed (its OK):

for m in app.iter_history('me'):
    print(datetime.fromtimestamp(m.date).strftime('%Y%m%d/%H:%M:%S'), m.message_id)

My out:

20200921/02:09:35 54074
20200920/12:56:04 54064
20200914/03:05:36 53510
20200912/21:36:49 53387
20200912/04:36:48 53362
20200912/04:36:41 53361

With offset_date only everything works fine, and messages limiting by creation date:

offset = int(datetime(year=2020, month=9, day=14, hour=4).timestamp())
    for m in app.iter_history('me', offset_date=offset):
        print(datetime.fromtimestamp(m.date).strftime('%Y%m%d/%H:%M:%S'), m.message_id)

Out:

20200914/03:05:36 53510
20200912/21:36:49 53387
20200912/04:36:48 53362
20200912/04:36:41 53361