Deleteing a property from an Immer Entity store doesn't work

[IAMtheIAM]

I'm submitting a...

[ ] Regression (a behavior that used to work and stopped working in a new release)
[x] Bug report  
[ ] Performance issue
[ ] Feature request
[ ] Documentation issue or request
[ ] Support request
[ ] Other... Please describe:

Current behavior

// Store config
@StoreConfig({
    name: 'my-store', producerFn: produce, resettable: true
})

// Delete property from stat
        this.store.update((state: StoreModel) => {
            delete state.myProp;
        });

Expected behavior

state.myProp should no longer exist, however, it remains there unchanged.

Minimal reproduction of the problem with instructions

Run above code, notice it doesn't delete the property.

What is the motivation / use case for changing the behavior?

Environment

Angular version: Vue 2.6.11


Browser:
- [ ] Chrome (desktop) version XX
- [ ] Chrome (Android) version XX
- [ ] Chrome (iOS) version XX
- [x] Firefox version 85.0.2 (64-bit)
- [ ] Safari (desktop) version XX
- [ ] Safari (iOS) version XX
- [ ] IE version XX
- [ ] Edge version XX
 
For Tooling issues:
- Node version: XX  
- Platform:  

Others:

[NetanelBasal]

Can you first try it by using plain immer?