Shopify-Buy Client Checkout addLineItems 500 error

Hi,

I’m trying to add a line item to a cart created by the shopify-buy client, but the call keeps failing.

yield call(() => shopifyClient.checkout.addLineItems(cart.id, [{variantId: `gid://shopify/ProductVariant/${id}`, quantity: 1}]));

The most recent error message is

"Internal error. Looks like something went wrong on our end.\nRequest ID: f87fbbbb-22c2-44bc-b58a-6786bcfb6dfb (include this in support requests)."

This is working targeting in one of my stores, but not the other…does anyone have any ideas on how to trouble shoot this?