Got lucky at the Malian border

When I was returning to Mali from Burkina Faso, I thought I was going to need to buy a 5-day entry visa for CFA15,000 at the border and then extend it to a full 30-day visa in Bamako, Mali. But, to my surprise, the border official said my old Malian visa was still good, so I only paid CFA1,000 to enter Mali. I believe they clearly misunderstood my old Malian visa: it is a single-entry visa and valid for 1 month. Since I'd already entered AND exited Mali with that visa, I should have been required to get a new one on my second visit. At the same time when I was at the Mali/Burkina Faso border, there were also 2 Americans, 2 Brits and 1 German, and they were all made to pay CFA15,000 to buy a new visa. Whatever the reason was, I felt very lucky, or, maybe they just liked my smile :D

Now I'm back in Mali, I just hope that every other official would think the same, and I would not encounter any problem when leaving.