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[wicked hinge]

Please define "doesn't work". Do you get a compilation error? A runtime error? If so, what does it say? If not, how does it "not work"?

Please post a complete minimal reproduction in a stackblitz. I can't understand what you're saying. But I'm going to bed anyway, so that'll be for later, or for someone else.

[torpid oxide]

Maybe

this.crewInfo.at(index).get('indicator').setValidators(Validators.required);```

[torn stag]

Deleted