This is a bug that's been occurring for me for the past few updates. I've had no trouble overall with this before.

So, I am currently building on my project in a creative world, and when I activate RTX (specifically the JG RTX texture pack) everything works completely fine. But when I join the world again with normal texture and no RTX, a few blocks are completely miscolored. That includes Sea Lantern, Prismarine, Lava, Prismarine Stairs, (every prismarine type block) 

The same thing happened when I tried the Vanilla RTX texture pack. This time after I rejoin without RTX the same blocks are miscolored, but a different color this time.

Then later on the same thing happens (with RTX on) this time. The lava turned green one time, the other time blue, and then completely black, not emitting any light whatsoever. 

As said, I have never had any problems with this before, it happens on multiple worlds too.