Add dynamic custom fee to the subscription checkout

Hello,

I am using a 3rd party shipping method via API. I have successfully added the CUSTOM shipping price however it only works for NON-SUBSCRIPTION products.

It simply doesn’t add the custom fee into the recurring totals. May I know how to add a custom fee into the Recurring totals, please?

Stucked here for 5 days already.. Pls help. thanks ??