[BUG] - Error: error creating server: gave up after 4 attempts, last error unavailable (resp == nil)

[shamblesides]

Describe the bug
I was able to use the terraform provider to create vultr instances a few days ago but now it doesn't seem to work. I get the error in the title consistently.

Plan: 1 to add, 0 to change, 0 to destroy.

Do you want to perform these actions?
  Terraform will perform the actions described above.
  Only 'yes' will be accepted to approve.

  Enter a value: yes

vultr_instance.my_server: Creating...

Error: error creating server: gave up after 4 attempts, last error unavailable (resp == nil)

To Reproduce
I'm not sure how to reproduce it, sorry. It's still happening on my machine.

Desktop (please complete the following information where applicable:

• OS: Xubuntu 20.04

$ terraform -v
Terraform v0.14.6
+ provider registry.terraform.io/vultr/vultr v2.1.3

Additional context

A few days ago, I did terraform init and set things, up, and was able to successfully run terraform apply, terraform import and terraform destroy to modify my infrastructure.

My config file, vultr.tf: (trying terraform validate returns that it is valid)

terraform {
  required_providers {
    vultr = {
      source = "vultr/vultr"
      version = "2.1.3"
    }
  }
}

provider "vultr" {
  api_key = file("~/.config/vultr-key")
}

resource "vultr_instance" "my_server" {
  region = "atl"
  plan = "vhf-1c-1gb"
  os_id = "391" # fedora-coreos
  hostname = "core1"
  user_data = filebase64("${path.module}/core1.ign")
}

[shamblesides]

Sorry, this was actually related to my own config, and not even really related to vultr. Specifying the api_key in the vultr provider using ~ won't work. Also I had a newline in my file that had the key in it. Maybe there's better ways to store and specify the API key anyway so I think I'm going to have to learn more about terraform... sorry for the noise!