500 error deactivating stack

When clicking the “stop” icon on the root level of a stack, I get the following error in the console:

POST https://xx/v1/environments/1e1/?action=deactivateservices 500 (OK)

And this response:

{"id":"cbe1697c-10ba-4603-8af3-591f1c3234ce","type":"error","links":{},"actions":{},"status":500,"code":"Internal Server Error","message":"Internal Server Error","detail":null}

Anyone else seen that?

I have not been able to reproduce this.