A window “Check your passwords” after axios request

After registering on the site, such a window pops up.

“Check your passwords. A data breach on a site exposed your password…”

Requests on server look like this:

import * as axios from 'axios'

const instance = axios.create({
    withCredentials: true,
    baseURL: 'api',
    headers: {
        'Content-Type': 'application/json'
    }
})

export const API = {
    signAPI : {
        signUp: (email, password, name, surname, username) => {
            return instance.post(`users/sign`, {email, password, name, surname, username})
                .then(response => {
                    return response
                })
        },
}

Perhaps I should pass some additional headers?