They are probably asking for your Google account password.
The PIN is probably the same as the 4 digit PIN you use when calling in to make changes to your account. You may be able to call CS as see if they can reset it or send it to you.
I can help you reset your password and view your upgrade eligibility date! How are you requesting your upgrade information? Via a call to customer service, online or through your mobile application? Please share, so I may advise the appropriate steps to reset. Please keep in mind you can easily view your upgrade date by dialing #UPG send from your mobile device and you will receive a free text with your upgrade date. I look forward to hearing from you soon! Thank you!
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