I also have LetsEncrypt installed. Here is the full error:
FastCGI sent in stderr: "PHP message: PHP Warning: An unexpected error occurred. Something may be wrong with WordPress.org or this server configuration. WordPress could not establish a secure connection to WordPress.org. Please contact your server administrator.
Everything was working fine up until a few hours ago. I tried to search online for a solution but couldn’t find one.
This error is preventing me from downloading and installing plugins.
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