There was an attempted coup in Venezuela. It was a whopping 10 soldiers and a retired general. There were others implicated, of course, politicians and business people. But their plan was to attack the presidential palace, among other targets.
In 2004, there was an attempted coup in Equatorial Guinea, which was intercepted by police and 79 soldiers were arrested (in two different countries). Most recently in Gambia, a small group attacked the presidential palace. Reports are the fighting was much more difficult than they expected.
Even had any of these coups successfully captured a presidential compound and managed to kidnap the president, they don’t control the government. What makes them think that would work? The rest of the government isn’t going to install a puppet regime for 10 people, presidential hostage or not.