AWS Lightsail certificates

Question

I have a question about AWS Lightsail CONTAINER service certificates.
I´m new to this stuff so please bear with me.
I successfully created a container service. I now want to attach a custom domain. Lets say abc.com. I bought this domain at some registrar (not AWS). In AWS lightsail I generated a certificate for both abc.com and www.abc.com. I then configured the DNS records at my registrar account. This certificate is then successfully verified. When I try to attach this certificate, it fails with error "Duplicated domains provided for service". So it is not possible to attach a certificate for both abc.com and www.abc.com. I also can´t create two separate certificate, as in Lighsail you can attach only one certificate. When I try to create the certificate for only abc.com and attach it, this works, and the url is also trusted. But when I enter www.abc.com it naturaly fails (meaning its considered to be a dangerous website) because the certificate is missing. I also tried to configure my DNS records to redirect everything from www.abc.com to abc.com, but this also results in a untrusted web.
My ultimate question is, how do I attach a certificate in AWS Lightsail for abc.com and www.abc.com or what other method I have to use so that both URLs are trusted. Thank you.