Is this a scam email

[ldbdo]

I start a transaction with a Buyer using escrow.com. We completed the first of four milestones.

Before making wire transfer to my account, a person at escrow.com sent me an email as follow:

Hello,

Escrow.com is prepared to release funds for Milestone #1 for this transaction.

Considering the $40 fee for each wire sent, please reply confirming whether you wish for Escrow.com to hold funds in escrow for one wire fee at the close of the transaction, or if you wish for funds to be disbursed as each Milestone is accepted by the Buyer.

If we may be of assistance in any way please let us know. Thank you!

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I confirmed in which I want to send money as separated milestone. Escrow then send me money for the first milestone with $10 less then the must-be amount. Next, I contact this escrow person, then he replied as following

Hello,,

I’m glad you received it so quickly – and apparently I shorted you $10? I’m very sorry, not sure what I was looking at! We’ll include the $10 in the next payment. Sincere apologies for that!
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I imagined that escrow should do this automatically and there should not be a mistake like this.

My concerns is
- Is this real escrow person to contact me?
- Should I trust escrow?

Any advise?

Thank you,