Stasis App Not Registered error in CLI using ARI

I am using the ari-py library to connect an internal web app to Asterisk. My Stasis App is called “routes”, and registered as such in both my Python module as well as extensions.conf.

Despite this, I am getting the error ERROR[9598][C-00000001]: res_stasis.c:1203 stasis_app_exec: Stasis App 'routes' not registered when I try to dial test extension 1000 from my softphone.

In the past when learning the ARI interface, I got this error when I forgot to add the Stasis function to the dialplan, however that is not the case here.

The main Python method has:

client.on_channel_event("StasisStart", stasis_start) client.on_channel_event("StasisEnd", stasis_end) client.run(apps="routes")

The dialplan has:

[aritest]
exten => 1000,1,NoOp()
same => n,Answer()
same => n,Stasis(routes)
same => n,HangUp  

Am I missing something? Tried reloading the dialplan as well as core reload / reboot of the Asterisk server and nothing made a difference.