adyen-ios: [BUG] Show 3DS challenge fails: Message element defined as required is missing from the message

Describe the bug I am getting an error trying to show challenge:

{
	"acsTransID": "b676f6e4-47ef-4359-a070-70f2f9a12953",
	"errorComponent": "C",
	"errorDescription": "Message element defined as required is missing from the message.",
	"messageVersion": "2.1.0",
	"errorMessageType": "CRes",
	"errorCode": "201",
	"errorDetail": "oobContinueLabel",
	"threeDSServerTransID": "4188320e-b3fe-4e92-bbfc-562972c93108",
	"sdkTransID": "1721ade0-88e4-434b-ae19-2b55bb9acf0b",
	"messageType": "Erro"
}

To Reproduce Using Adyen DropIn 3.8.0 (of even 3.7.0), when I try to make a payment using Pleo credit card (MC), the DropIn tries to open the 3DS challenge page, it fails with the above error.

In fact, I can see two calls to https://3ds-a.live.ext.prod.enfuce.com

first one Request: eyJraWQiOiI2OTdjYWJiNC1kN2YxLTRhZmEtOW.... Response: eyJraWQiOiI2OTdjYWJiNC1kN2YxLTR....

The second one fails with the above error

Expected behavior The SDK should display the 3DS challenge page.

Screenshots If applicable, add screenshots to help explain your problem.

Smartphone (please complete the following information):

• Device: iPhone 8
• OS: iOS 14.2
• SDK Version 3.8.0

Additional context We used to use ‘Adyen’, ‘3.6.0’ version and we used to get a different error

{
	"messageType":"Erro"
	,"messageVersion":"2.2.0"
	,"threeDSServerTransID":"7281478a-317b-426f-99fb-d16c9755d0a2"
	,"acsTransID":"b7e90cb8-a2ec-43fa-8e41-bb46d9137cab"
	,"dsTransID":"35d629ac-f230-4d39-8dc6-8a42df60ddf7"
	,"sdkTransID":"f2911aa5-c42d-4b4c-bcbc-5f553598b579"
	,"errorCode":"203"
	,"errorDescription":"Invalid format"
	,"errorDetail":"Field [messageVersion] has a wrong value [2.2.0]"
	,"errorMessageType":"CReq","errorComponent":"A"
}

I have to try to upgrade to 3.7.0 and 3.8.0 which result in a different error. (which is mentioned above Message element defined as required is missing from the message

To be clear, I just updated the version in the Pod and did not make any modification to the code (3.6.0 -> 3.7.0)

On Friday I managed to make a successful transaction, however today it failed ( no code change )

I have also raised an issue on Android as well https://github.com/Adyen/adyen-3ds2-android/issues/38