3D Secure problem

Hi, within last month we receive a lot of errors as below:
“Amount must match the 3D Secure authorization amount.”
So the customer see different price on our website, and different, usually lower during 3DS verification. As a result amounts don’t match and transaction is beeing rejected.
We have contacted with BrainTree support, and they responded us more about our transactions errors:

“Error 91584 -The merchant account specified when creating the transaction must match the merchant account specified when generating the client token. If you do not specify a merchant account ID, your default merchant account will be used.
For this error in our logs, I can see a transaction originally coming from mdbootstrapUSD, but then being claimed as mdbootstrapEUR with 3D Secure.

Error 91585 – The amount used for 3D Secure verification must match the amount used to create the transaction.
For this error in our logs, I can see a transaction at time stamp 04/02/2019 17:12:02
for $71, but then is submitted with 3D Secure for $63.

These 3DSecure errors are being triggered by errors in your checkout flow”

We don’t know why the amounts from checkout is different than 3DSecure.

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