# How to add a field where customers can enter their phone number?
{% hint style="warning" %}
**This is a Premium feature of Cowlendar.** You need to upgrade your plan if you want to use this feature and you are a free user of Cowlendar.
{% endhint %}
**Steps to add a custom field where a customer can enter there phone number**
1. In your Shopify admin bashboard look at the left panel and click on the **Apps.**
2. Click on **Cowlendar.**
3. Click on **My Servic**e.
4. Click **Edit** on the service you want to add a question to.
5. Click on the **Advanced tab.**
6. In the advanced tab you will scroll down and **find the Custom question section.**
7. Click on **What contact information to ask?**
8. Select **"Email + Phone" or "Phone".**
9. Click **Edit** on the **Phone question.**
10. Set your **default country.**
11. Click **Save.**
12. Click **Update.**
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