Unable to change settings

I have the common problem which is that I cannot change Better-WP-Security settings via the plugin menu due to the error “You do not have sufficient permissions to access this page.” However unlike other WordPress installations I am unable to change the settings via the security option either on the left menu in the WordPress dashboard because for some peculiar reason the security option is not there / visible. Anyone know why this would be and what the fix might be ?

https://www.ads-software.com/extend/plugins/better-wp-security/