Untraceable error with Source Map

Hi all,
We use angular 4 in our production app and sentry. I am quite sure i have followed sentry CLI tutorial as much as i can.
Am i doing something wrong? My upload steps are as follows:

sentry-cli releases -o orgName -p projectNAme new 1.0.0.2

sentry-cli releases -o orgName -p projectNAme 1.0.0.2 upload-sourcemaps C:\www\frontend\assets\prod-js

i can see the release and source map all starting with ~/ but then the error are logged its not helpful, transaction field states

/assets/f7587e46/main.bundle.js in l at line 1:1819795

I will be highly grateful for your help.

Kind regards
Jamiu