Since you are using LightSail with Bitnami image, please please please use your Bitnami image provided script to request and install a certificate.
Bitnami AWS cert-tool link: https://docs.bitnami.com/aws/faq/administration/generate-configure-certificate-letsencrypt/
I mean, it’s even pinned here: Using Bitnami? Please see Bitnami's documentation!