Some Displays have two colors and a small space between the top 16 lines and the following lines.
If you create a picture make sure you don't mix these two areas or it will look funny.
Or create pictures which take advantage out of the two colors.
Links to other PIX Repos
https://github.com/ingloriond/MiSter_I2C_Logos/tree/main/i2c2oled_pix