"502 Bad Gateway"

After I installed the premium version of AVG softwares, some websites won't load. I see the following message:

"502 Bad Gateway
Certificate verify failed: unable to get local issuer certificate"

After reading a few posts in this forum, I tried the following solutions: (1) restarting my computer; (2) removing and re-installing all the AVG software; (3) trying to open it using Chrome and Safari; and (4) turning off the protection of the browser. None of these worked.

I also tried to open the same websites using other devices (which are not protected by AVG). The websites are working perfectly fine.

How should I proceed?

Hello Joao,
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