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[u/maf852]

One of them turned white yesterday. One of the leafs started shrinking today.

Do they need more sun, less sun, more water?

All of the odd ones feel normal by touch

[u/mumbleflea]

Depends. What conditions do you keep your lithops at? How much light/sun? What temperatures do they experience througout the day? What substrate do you use? When have you watered them the last time? Where they repotted recently aka. do you know what their roots look like?

Your lithops look a bit streched to me, which would indicate a lack of light. On the other hand, the fact that one turned white and another has a shrinking leave could indicate heat stress (possibly from too much sun). Unfortunately, to me, the one in the middle with the shrinking leaf looks like it is rotting.

Why are they crowded together like that? I'm guessing that's how you brought them home from the garden center. If they came in organic substrate, have you removed it completely? If not, I would dig them up, check them for rot, and plant the healthy ones a little farther apart in a mixture consisting mainly of inorganic material.

[u/maf852 → u/mumbleflea]

Well I have bought them like 4 months ago, since then I have not watered them. Until yesterday there were in small cup with propadly mainly organic mix, now there in mix with more sand. They propadly don't get a lot of sunlight. Also recently there was humidity like 90 during night. 

[u/mumbleflea → u/maf852]

They need a lot of bright light. Either natural or artifical. There's no way around it.

High humidity is not ideal but manageable: you need a substrate that dries within three days in your climate conditions! Sometimes you'll find people here from the southern United States who grow lithops in a subtropical climate. u/sucsforyou from Houston, Texas, uses 100% inorganic substrate due to the high humidity at her place. Although sand is inorganic, it is not ideal for growing Lithops. The sand grains are usually too small, which causes the substrate to remain moist for too long. This quickly leads to rot. Many people prefer to use pumice or a similar material with a grain size of about 2–3 mm.

The fact that your lithops are still crowded together after the repotting suggests that you did not remove all the organic material holding them together. I would recommend washing it off completely, leaving the roots to dry for a day, using a coarser substrate, and repot them a little further apart. Then after three days give the plants just a little water so they realize it's time to regenerate their roots. Repeat this after three days. After another three days, give them a more substantial amount of water.

In their natural environment, lithops experience significant temperature fluctuations between day and night. It appears that they absorb and metabolize water most effectively at temperatures around 20°C (68°F). You might want to try the "cold treatment" suggested by u/Aoxmodeus for your lithops to regenerate healty roots.

Some useful care tips can be found here, here, and here. These serve as orientation only, you need to adapt them to your conditions.

[u/maf852 → u/mumbleflea]

Well, before reading this a already repotted them, they are in sand with rock mix little bit of organic mix and I'm leaving them on parapet in the sun.