AWS has machine types that require ENA Support. You can run AWS CLI to find out if instance is ENA enabled.

aws ec2 describe-instances \
--instance-id i-xxxxxxxxxxxxxxxxx \
--profile default \
--region us-east-1 \
--query 'Reservations[].Instances[].EnaSupport'

Login to the instance and verify.

sudo lspci | grep -i Amazon

List driver details.

modinfo nvme

Verify modules loaded at startup.

lsmod | grep nvme
lsmod | grep ena

If ENA drivers are missing, install them.

yum install pciutils