Multiple items on SDA/SCL pins? Mega 2560

The problem is, the application Im using relys on pins 20 and 21 but they are being used as standard digital pins and I can not change them.

There are multiple I2C peripherals: maybe PD0/PD1?

https://duino4projects.com/wp-content/uploads/2013/04/ardunio_mega_pinout.jpg