Build Failure on Heroku

[mrchristopher124]

We have been running an Elixir based site on Heroku for quite some time. We make updates to the site every few months. We last made an update back in December 2018 and did not have any issues. Unfortunately, we recently tried to publish a new update for our site and ran into a strange build error. We've tried a number of things to resolve. We did not change anything with respect to the Heroku stack or build packs. Here is the error:

npm ERR! Linux 4.4.0-1038-aws
npm ERR! argv "/tmp/build_938959a090592f7c5e7bf4b1770b7816/.heroku/node/bin/node" "/tmp/build_938959a090592f7c5e7bf4b1770b7816/.heroku/node/bin/npm" "run" "deploy"
npm ERR! node v6.9.2
npm ERR! npm v3.10.9

   npm ERR! missing script: deploy
   npm ERR!
   npm ERR! If you need help, you may report this error at:
   npm ERR!     <https://github.com/npm/npm/issues>
   
   npm ERR! Please include the following file with any support request:
   npm ERR!     /tmp/build_938959a090592f7c5e7bf4b1770b7816/npm-debug.log

! Push rejected, failed to compile Phoenix app.
! Push failed

This is on Heroku's cedar-14 stack. Grateful for any help!

[mrchristopher124]

Additional note:

Ok, but now we have another issue, project builds, but server didn't starts:
according to the logs:
2019-04-12T13:36:51.896854+00:00 heroku[web.1]: Starting process with command mix phx.server
2019-04-12T13:37:05.482034+00:00 heroku[web.1]: State changed from starting to crashed
2019-04-12T13:37:05.451007+00:00 heroku[web.1]: Process exited with status 1
2019-04-12T13:37:05.362304+00:00 app[web.1]: ** (Mix) The task "phx.server" could not be found. Did you mean "phoenix.server"? (edited)
It cant recognize the mix phx.server command, this command starts the Phoenix server

[HashNuke]

@mrchristopher124 Are you still facing this issue?

[alexfinnarn]

I would close the issue now...thought I might find something about issues I'm having in here, but it's confusing. My guess is phoenx.server would have worked. I'm new so I'm not sure when phoenix. became phx.