ClosedBit error docs

CB_ERR_NULL

Required value was missing. A native call received a missing pointer, buffer, or required value.

Why it happens

A native call received a missing pointer, buffer, or required value.

How to fix it

Rebuild from Studio and make sure the app passes real data into the API.

Copy-paste fix pattern
check
compile cba app.cbp app.cba small compute
Runtime and Studio now show this kind of page from the error dialog: plain message first, stable code second, original details third.