Cannot go on to USPS.com - says I'm not allowed

Hello Marie,
Thank you for contacting AVG Community Support.
We are really sorry to know that you are unable to access websiste.
We apologies for the inconvenience caused. We'll certainly check and help you out.
Could you please let us know are you still facing the issue?
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Please refer this article to disable AVG: | AVG (https://support.avg.com/SupportArticleView?l=en&urlName=disable-avg-antivirus&q=disable&supportType=home)
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I have been using USPS.com for years for getting Informed Mail daily, for finding zip codes, for tracking.  Now when I go onto USPS.com I get this message: 
You do not have permission to access this page If you have found this page in error, please contact support Reference:10399565866452248958868037686727193979020034968299102359
As a result, I cannot check tracking numbers, look up a zip code, or check my Informed Mail daily.
Does anyone have a solution or understands what's going on?
Thank you!

Hello Marie,
Thank you for contacting AVG Community Support.
We are really sorry to know that you are unable to access websiste.
We apologies for the inconvenience caused. We'll certainly check and help you out.
Could you please let us know are you still facing the issue?
If so, how you suspect AVG is causing the issue?
We would request you to temporarily disable AVG and see if the issue will exist.
Please refer this article to disable AVG: | AVG (https://support.avg.com/SupportArticleView?l=en&urlName=disable-avg-antivirus&q=disable&supportType=home)
If you are still facing any issue, please let us know we will help you to resolve the issue.

Thank you and keep us updated.