Cannot delete an EC2 hosts from Hosts

I have a host that fails to delete which I added via the EC2 Compute plugin

Expected outcome:
Hosts should be removed from Hosts view

Foreman and Proxy versions:
Foreman and Proxy plugin versions:
Distribution and version:
Centos 7
Other relevant data:
I got this from production.log

2020-06-12T13:07:22 [W|app|539f3d02] ERF12-6886 [ProxyAPI::ProxyException]: Unable to remove host from known hosts ([TypeError]: no implicit conversion of nil into String) for proxy https://foreman:9090/ssh
2020-06-12T13:07:22 [W|app|539f3d02] Rolling back due to a problem: [#<Orchestration::Task:0x00007fde8fa460d0 @name="Remove SSH known hosts for", @id="ssh_remove_known_hosts_interface__1", @status="failed", @priority=200, @action=[#<Nic::Managed id: 10, mac: nil, ip: nil, type: "Nic::Managed", name: "", host_id: 3, subnet_id: nil, domain_id: 2, attrs: {}, created_at: "2020-06-02 09:43:03", updated_at: "2020-06-02 09:43:03", provider: nil, username: nil, password: nil, virtual: false, link: true, identifier: "", tag: "", attached_to: "", managed: true, mode: "balance-rr", attached_devices: "", bond_options: "", primary: true, provision: true, compute_attributes: {}, execution: true, ip6: "", subnet6_id: nil>, :drop_from_known_hosts, [1, nil]], @created=1591967242.19267, @timestamp=2020-06-12 13:07:22 UTC>]