Hi Mikba and welcome to the forum. You should really read this before posting a message so you understand the etiquette and how to put your code in a code tags to make it more readable.
I have not looked at your code but a quick search on the RC552 seems to indicate it's a 3.3V board so that's a good start.
It would help if you had posted links to the Lolin32 OLED board your using and maybe give some details on the settings your using to program it. If your using the "Wemos Lolin32" board definition (I cannot see one for the OLED board) then the SPI pins your using (SCLK (SCK) = 14, MISO = 12, MOSI = 13, SS (SDA?) = 15, RST = 5) are probably wrong.
If your board looks like the below image then I think the wiring should be...
SCK to CL
MISO to SO
MOSI to SI
SS to 5
