Custom Helper documentation, creating a helper function not working

Currently I’m getting a `Missing Helper` method when trying to launch the theme preview.
`module.exports = function (Handlebars) {
return {
verifyTagName: function(tagName) {
let tagNamesNotToUse = [‘Full Time’, ‘Apprenticeship’, ‘Temp’]
tagNamesNotToUse.forEach(tag => {
if(tag === tagName){
return false;
}
})
return true;
}
};
};

`
I have the above code in `/themes/starter/helper.js`. I also change the configuration to the`config.json` file.

“renderer”: {
`”includeHandlebarsInHelpers”: true,`

As per the documentation shown here https://getpublii.com/dev/how-to-create-custom-handlebars-helpers/

However I get the error from this code.
`
{{#each @website.contentStructure.tags as |tag|}}
{{#verifyTagName tag.name}}
{{#if tag.postsNumber}}

{{ tag.name }}

{{/if}}

{{#each this.posts}}
• 
  {{title}}
  

{{/each}}

{{/verifyTagName}}
{{/each}}

`
The error is `MIssing: Helper`. How can I go about solving this?