Bad CSRF with mailgun replies

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8

I followed these directions exactly, and am getting the following error at mailgun. Should I assume that I need to migrate away from mailgun to receive reply emails?

Also, I’m confused what the mailgun api key is used for. Says it’s used to verify webhook messages. Can someone elaborate?

{
"severity": "temporary",
"tags": [],
"storage": {
    "url": "https://se.api.mailgun.net/v3/domains/reply.volyoom.fit/messages/eyJwIjpmYWxzZSwiayI6IjhiYTFjMTI0LWVhNmQtNDcxZC05MzU5LTNiNzhjZGY2MGJmYSIsInMiOiJkNDFhMjFlMDRmIiwiYyI6InRhbmtiIn0=",
    "key": "REMOVED"
},
"delivery-status": {
    "attempt-no": 1,
    "description": "[\"BAD CSRF\"]",
    "session-seconds": 0.07819604873657227,
    "retry-seconds": 600,
    "code": 403,
    "message": "[\"BAD CSRF\"]"
},
"recipient-domain": "REMOVED",
"id": "QRcFjJ3NSKu0Hn9pfPnGyQ",
"campaigns": [],
"reason": "generic",
"user-variables": {},
"flags": {
    "is-routed": false,
    "is-authenticated": false,
    "is-system-test": false,
    "is-test-mode": false
},
"log-level": "warn",
"timestamp": 1508087126.237296,
"envelope": {
    "sender": "REMOVED",
    "transport": "http",
    "targets": "REMOVED/admin/email/handle_mail"
},
"message": {
    "headers": {
        "to": "REMOVED Forum <replies+ddcd9246b485715a803756190c86e6e5@REMOVED>",
        "message-id": "ADBE049D-0179-4B3C-813A-517A02741FBD@monroeresidential.com",
        "from": "Drew Friestedt <REMOVED>",
        "subject": "Re: [REMOVED Forum] [Zwift] This is a test topic with email reply"
    },
    "attachments": [],
    "size": 7044
},
"recipient": "REMOVED/admin/email/handle_mail",
"event": "failed"