I want to correct the custom data from facebook capi and external_id issue also

I am facing two issues with Facebook capi

First Issue

In purchase event, the currency value automatically coming without in my control

how I would correct this problem
Screenshot (175)

You can see i passed these value in server-side
Screenshot (176)
to send facebook,

Screenshot (180)

Screenshot (178)

tell me the solution how i would correct this problem.

Second Issue

In Facebook event manager diagnostic panel for all events, I get the error like this external_id did not match the pixel

Screenshot (179)

But, I did not know how to send the external_id from the server-side and also from the pixel, i totally follow your tutorial to setup Gtm Server client side

To fix the first issue disable Send All from Data Layer inside the Data Tag.

To fix the second issue, try to remove the User ID parameter from all Facebook server tags. And then mark errors in the Events manager as resolved, if this error will continue Facebook will send a new notification.

First issue is resolved

Second issue, i will try as you said wait for Facebook any new notifications

Thanks @Ira