I almost always immediately transplant purchased cacti.
In my experience, this is not reflected even when transplanting cacti with buds on their flowering.
They are blooming.
I do not think that what I do when transplanting a cactus is news, but I hope that this can be useful for beginner lovers.
Having taken out the cactus from the pot, I wash it under a rather warm shower.
Then I dry it (but not under the sun) for 3-4 days in the cool season and 2 days in the summer.
Then sprinkle it with crushed charcoal or activatedcoal.
And after 2-3 hours I plant in a pot washed with hot water, filled with earth for cacti.
I produce watering in 3-4 days.
If the cactus has buds, then water should not fall on them.
If water gets on them, there is a big possibility that they will not bloom.
The photos I were taken with a Lenovo TAB 2 A10-70L tablet
Gymnocalycium ragonesei is only 2.5 cm high with a diameter of 5 cm.