209 Invoke Validation Failed - Different Chat Contexts

Hi there,

I have a strange issue.
When using Teams (occurs in both Desktop and Web clients), I get this error when trying to call one of our APIs from an Adaptive Card:

{
    "errorCode": 0,
    "message": "Invoke validation failed. User forbidden to perform action",
    "standardizedError": {
        "errorCode": 209,
        "errorSubCode": 1,
        "errorDescription": "Invoke validation failed. User forbidden to perform action"
    }
}

It only happens when in a 1:1 chat and a group chat context. The error does not happen when interacting with the bot directly.

Here is the manifest:

{
   "$schema":"https://developer.microsoft.com/en-us/json-schemas/teams/v1.16/MicrosoftTeams.schema.json",
   "manifestVersion":"1.16",
   "version":"1.2.0",
   "id":"{{.AppID}}",
   "localizationInfo":{
      "defaultLanguageTag":"en-gb",
      "additionalLanguages":[
         
      ]
   },
   "developer":{
      "name":"REDACTED",
      "websiteUrl":"REDACTED",
      "privacyUrl":"REDACTED",
      "termsOfUseUrl":"REDACTED"
   },
   "icons":{
      "color":"color.png",
      "outline":"outline.png"
   },
   "name":{
      "short":"{{.AppName}}",
      "full":"{{.AppName}}"
   },
   "description":{
      "short":"REDACTED",
      "full":"REDACTED"
   },
   "accentColor":"#00bd00",
   "configurableTabs":[
      
   ],
   "staticTabs":[
      
   ],
   "bots":[
      {
         "botId":"{{.AppID}}",
         "scopes":[
            "personal",
            "groupChat",
            "team"
         ],
         "needsChannelSelector":false,
         "isNotificationOnly":false,
         "supportsFiles":false,
         "supportsCalling":false,
         "supportsVideo":false,
         "commandLists":[
            {
               "scopes":[
                  "personal",
                  "groupChat",
                  "team"
               ],
               "commands":[
                  
               ]
            }
         ]
      }
   ],
   "composeExtensions":[
      {
         "botId":"{{.AppID}}",
         "commands":[
            {
               "id":"REDACTED",
               "context":[
                  "commandBox",
                  "compose",
                  "message"
               ],
               "description":"REDACTED",
               "title":"REDACTED",
               "type":"action",
               "fetchTask":true
            }
         ]
      }
   ],
   "permissions":[
      "identity",
      "messageTeamMembers"
   ],
   "devicePermissions":[
      
   ],
   "validDomains":[
      "REDACTED",
      "REDACTED"
   ],
   "showLoadingIndicator":false,
   "isFullScreen":false,
   "activities":{
      
   },
   "defaultInstallScope":"personal"
}

Note I have added "personal", "groupChat" and "team" scopes, which I thought would sort it.

Thanks.