Help with Facebook Tax Info Process

I am currently facing issues completing the 'Add your tax info to get paid' process on Facebook. My partnership firm based in India is at the final step where Form W-8IMY needs to be filled out.

I have partially completed the form, but I'm unable to find the upload option for it.

I need assistance with:
- Identifying the correct upload option on Facebook
- Completing Form W-8IMY

Skills and experience ideal for this task include:
- Familiarity with Facebook's tax processes
- Understanding of Form W-8IMY
- Experience in assisting with tax forms