HELP… RabbitMQ enable rabbitmq_prometheus Error

I was trying to enable this plug via rabbitmq-plugins enable rabbitmq_prometheus and it failed with the following error.

Applying plugin configuration to rabbit@portal…
Stack trace:

** (CaseClauseError) no case clause matching: {:error, {:cannot_read_enabled_plugins_file, ‘/etc/rabbitmq/enabled_plugins’, :eacces}}
{:case_clause, {:error, {:cannot_read_enabled_plugins_file, ‘/etc/rabbitmq/enabled_plugins’, :eacces}}}

I am not getting an Error code 500 on my admin web portal. I tried to disable that plugin, but I get the same error.

How do I get this fixed. I cannot even find where the admin write logs its errors to see what I might be able to do.. HELP!!!