Addin Function After Sign Up

I used the below code but the slug not inserted to ‘PublicMembersData’ collection, please advise

import wixData from 'wix-data';

export function wixMembers_onMemberCreated(event) {
    return wixData.insert("PublicMembersData", {
        _id: event.entity._id,
        memberReference: event.entity._id,
        _owner: event.entity._id,
        filter: event.entity._id,
        slug: event.entity.profile.slug,
        nickname:  event.entity.profile.nickname,
    })
    .catch(err => {
        if(err.errorCode === "WDE0074") {
            return Promise.resolve("User_already_exists");
        }
    })
}