Add user to content restriction

I want to grant a user access to a restricted confluence cloud page. I used the (Documentation) Add user to content restriction for reference. But I am getting an error 401 (Unathorized)

export const grantPageAccess = async (pageId, accountId, operation) => {
    try {

        const response = await api.asUser()
            .requestConfluence(route`/wiki/rest/api/content/37703334532/restriction/byOperation/update/user/?accountId=12333523452452452`, {
            method: 'PUT',
            headers: {
                'Accept': 'application/json',
                'Content-Type': 'application/json',

        return response.status === 200;
    } catch (error) {
        console.log(`Error granting page restriction: ${error.message}`);
        return false;

Note: I hardcoded the pageId, account, and operation for testing purposes. My token is valid, I have permissions to grant access to the restricted content. This works when testing with Insomnia and Postman