Webhook topic headers missing

[WilloH]

I have an API integration with Shopify. I am using the official Node Shopify library. Very occasionally for a few hours, the Shopify webhook stops containing necessary header data. The Shopify library triggers the error: "Missing one or more of the required HTTP headers to process webhooks: [X-Shopify-Hmac-Sha256, X-Shopify-Topic, X-Shopify-Shop-Domain]". I can see that X-Shopify-Topic is missing. And then after sometime it will work again and everything will be back to normal. Unfortunately this breaks the integration and makes it unusuable, and causes us to lose out on important data.

Is there any information on how/why/when this occurs and how to mitigate it? I have searched the forums and found no specific information.