Postal Locations

Several years ago I mailed three letters at three different times. All three letters were "lost" in the mail. I now mail my items from the Moultrie post office.

I run a small business out of my home which I regularly utilize the USPS to
ship items (paid online shipping), small items that I can place in my mailbox
are logged in immediately upon pick up (Tracking Number entered) by my Mail
carrier. Larger Items I sometimes take to the Berlin Georgia Post Office (Zip
31722). Upon presenting the CLERK with the package(s) she has continually
refused to provide a receipt , ... I have dealt with this issue for over a
year, currently upon presenting packages with tracking numbers, she has now
failed to log them into the computer system i.e. ( EXAMPLE's -
9405509699939477XXXXXX and 9400109699937130XXXXXX, one is a Priority mail item
the other First Class Mail, both were presented on Wednesday (DEC 10) around
noon. My Integrity with my customers are put in jeopardy when I tell them I
Mailed them on a certain date and they fail to locate them upon search of a
tracking number.. Every time I respond to Berlin there is no one waiting in
line and the Clerk does not appear to be busy. I do not have this problem at
other USPS locations. Could you provide a remedy, or explain to me the
requirements of presenting shipping items to Postal Employees.... Please feel
free to contact me at anytime... Thank You "The Above Letter Sent to the Post Master General"