For a spacecraft orbiting a planet, orbital speed is inversely proportional to orbit radius. But speed must be increased to increase orbit radius?

For a spacecraft in orbit with radius $r$ with speed $v$ around a planet, centripetal force $F_C$ is provided by gravity:

$$\frac{GmM}{r^2}=\frac{mv^2}{r},$$

which simplifies to

$$\frac{GM}{r}=v^2.$$

This means that orbits closer to the planet are required to have greater speeds. However, if we want to move a spacecraft to a higher orbit, we have to increase the semimajor axis (adding energy to the orbit) by increasing velocity (source: FAA). How is this reconciled with the above equation?

gravity orbital-motion centripetal-force

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For a spacecraft orbiting a planet, orbital speed is inversely proportional to orbit radius. But speed must be increased to increase orbit radius?