I ran into a weird glitch twice so far where if I press the terraform for mining on a planet, it won't do anything, but once I zoom out it shows the planet terraformed, but no progress.
Upgrading the mines does nothing.
I cannot recall if the first time was done with the planet under the influence of a central business system upgrade, but the second time I can confirm it was under the sphere of influence of one before I terraformed it to a mining planet.