How to ingest pprof.Profile with customized labels in the samples?

I failed to ingest a pprof profile with some customized labels (call depth, call count, etc.), which is already proven to be parsable with go pprof tool. And the ingestion API also works fine after I removed these labels.

I didn’t see any feasible ways like adding query params to pass or register these labels for ingestion in the docs.

My curl lines and response as follow:

curl --data-binary @/$MYPATH/goxctrace/resource/test.pb.gz "http://localhost:4040/ingest?format=pprof&name=my.pprof.test"
{
    "code": "unknown",
    "message": "pushing IngestInput-pprof failed invalid_argument: invalid labels '{__delta__=\"false\", __name__=\"memory\", call depth=\"2\", count=\"69573\", pyroscope_spy=\"unknown\", real percentage=\"81.30%\", service_name=\"my.pprof.test\"}' with error: invalid label name 'call depth'"
}