External payment provider - Webview not appearing after clicking the button
I'm looking for a little help. We've developped an integration using the external payment provider API and the OAuth flow. We've tested it and installed it at customers and it's working. Still, we're facing problems for a specific customer. We've created the external payment provider (I have logs and kept track of the POST response, including the created external payment provider's Lightspeed assigned id), we've then added the payment button using Lightspeed's manager web app. The button correctly appears on the customer's screen. But when using it, the webview doesn't open. There's just a kind of pinpad opening.
Can someone help us in debugging what's going on?