sent 2 used watches back and only received credit for 1

How did you send them in? nTogether? You must initiate a separate trade-in for each product that you want to trade in and pack each trade-in product in a separate box. More information about how to trade-in or recycle your Apple product is available online.

How to prepare your iPhone or Apple Watch for trade-in - Apple Support

Rayvsabell wrote:

yes trade in. I sent them both back in the same box. If that’s the issue please send one back and I will resend it . I bought 2 new watches

We can't send you anything. We are not Apple. This is a user forum.

What do you mean for credit? Do you mean as a trade it? Only one trade in per purchase.