These far east I2C OLEDs contain strange resistors on the PCB. Some will work, others will not work.
From my personal experience, all these OLEDs work with 3.3V Boards. With 5V Boards, they may or may not work. I had both cases in my lab. You could try to use U8g2 Software Emulated I2C, which might help. It may also help to test with different voltage levels at VCC.
There are special ICs for this purpose (like this: https://www.nxp.com/docs/en/data-sheet/PCA9515.pdf) but these kind of resistor magic what we have on these inexpensive boards may or may not work. Adding a PCA9515 would obviously too exensive for the OLED supplier.
Oliver