Home Assistant Community Add-on: Grocy

That doesn’t sound like it is related to the Grocy add-on (this thread). The Grocy add-on doesn’t provide a specific service call, the community add-on does. I’d try to ask there: Grocy - Custom component and card(s)

That’s specific to the HA app, please ask there. Grocy only expects your input, no matter where it comes from (an app, you typing it, from a scanner…).