Action Details
Requirements and how-to articles for YouTube's action:

Verify Account
Verifying your account lets you upload videos longer than 15 minutes long, add custom thumbnails to your videos and do live streams.

Requirements
You need this to get it done:

Account Verification
Enter a phone number to be associated with your YouTube account, which will be used to send your verification code to.
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How-To Articles
A list of useful links for you:

1
YouTube Help - Verify Your Account By Phone
Instructions on how to verify your account.
Official
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