Rant-en-Dal SA Postal Services lock paid box

SA Postal Services do not sort their mail on a regular basis, thus mail become to much for box. Dawid, postmaster, at Rant-en-Dal wants to force me to take a Private Bag, which I cannot access after hours, which is the time when I pass this mailbox, due to a lot of mail. I pass this box twice a week with hardly any mail and then all of a sudden the box is locked. Was locked December 2015 after I already paid the 2016 fees early December. They do not do their job by placing a slip in the box for counter collection when there is a lot of mail. Spoke to a senior person in SA Postal and he said there is no ways they can force you to take a private bag, it is my choice. Dawid blames Herman and yet today, box locked again, Herman is still on leave since last year? Since Dawid became postmaster at Rant-en-Dal my mail has become a problem, never a problem with the previous post master, she even used to phone me with rate increases to warn me. We, making us of SA Postal Services, are paying their salaries and yet they want to stuff us around?