Please fill out the fields below so we can help you better. Note: you must provide your domain name to get help. Domain names for issued certificates are all made public in Certificate Transparency logs (e.g. https://crt.sh/?q=example.com), so withholding your domain name here does not increase secrecy, but only makes it harder for us to provide help.
Your certificate works correct with brandculture.africa, this is your certificate name.
But you have a redirect non-www -> www, your certificate doesn't have the www-entry.
So this is a mismatch.
Version 1: Remove the redirect (not good)
Version 2: Create a new certificate with -d brandculture.africa -d www.brandculture.africa, so you have one certificate with two domain names (better).
So visitors can use your site by typing non-www + www.