Ionic3 not working anymore?

I have been developing a new ionic4 app and all is working fine. I also have an ionic3 app and when I tried to run ionic serve I’m getting an error now:

PS C:\ionic\apps\ionic3\MedicalAnswers-admin> ionic serve
[WARN] Detected locally installed Ionic CLI, but it's too old--using global CLI.
> npm run ionic:serve -- --address --port 8100 --livereload-port 35729 --dev-logger-port 53703 --nobrowser
[npm] > LiveVault-admin-console@1.0.0 ionic:serve C:\ionic\apps\ionic3\MedicalAnswers-admin
[npm] > npm run serve "--address" "" "--port" "8100" "--livereload-port" "35729" "--dev-logger-port" "53703" "--nobrowser"
[npm] npm ERR! missing script: serve
[npm] npm ERR! A complete log of this run can be found in:
[npm] npm ERR!     C:\Users\gigoc\AppData\Roaming\npm-cache\_logs\2019-02-19T18_38_19_136Z-debug.log
[npm] npm ERR! code ELIFECYCLE
[npm] npm ERR! errno 1
[npm] npm ERR! LiveVault-admin-console@1.0.0 ionic:serve: `npm run serve "--address" "" "--port" "8100" "--livereload-port" "35729" "--dev-logger-port" "53703" "--nobrowser"`
[npm] npm ERR! Exit status 1
[npm] npm ERR!
[npm] npm ERR! Failed at the LiveVault-admin-console@1.0.0 ionic:serve script.
[npm] npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
[npm] npm ERR! A complete log of this run can be found in:
[npm] npm ERR!     C:\Users\gigoc\AppData\Roaming\npm-cache\_logs\2019-02-19T18_38_19_368Z-debug.log

[ERROR] npm has unexpectedly closed (exit code 1).

        The Ionic CLI will exit. Please check any output above for error details.

I have the same problem with ionic 3 and conference official app. Have you solved the issue?