Cannot delete ENI after delete the stack via Terraform

Hello. via terraform I've created a stack with EKS. On EKS I did setup aws-load-balancer-ingress-conotroller and traefik.

Before to destroy everything via terraform I didn't delete the 2 pods for my alb and traefik service.

Doing so I'm not able to delete the eni created by these process.

I'm root in my account and I run also the following command

aws ec2 detach-network-interface --attachment-id eni-attach-xxxxxxxx --force

An error occurred (AuthFailure) when calling the DetachNetworkInterface operation: You do not have permission to access the specified resource.

Also I've a basic account, so I cannot contact the support in order to ask them to delete for me.

Can please someone shed some light ?

Thanks