[Bug]: when the user does not enter his username, the submit button working

**Describe the bug**

when the user does not enter his username, the submit button working and In the white theme Contact-Us card is not good-friendly

**Expected behavior**

user should enter his full details in contact us page

**Screenshots**
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**Actual behavior:**

https://github.com/akshitagupta15june/PetMe/assets/121508628/aa03e5f3-a5f0-4eed-93d8-46bccee3edf9

**Expected behavior:**


**I am GSSOC24 Contributor
please assign me, I would like to work on it**

**Desktop (please complete the following information):**
- OS: [e.g. iOS]
- Browser [e.g. chrome, safari]
- Version [e.g. 22]

**Smartphone (please complete the following information):**
- Device: [e.g. iPhone6]
- OS: [e.g. iOS8.1]
- Browser [e.g. stock browser, safari]
- Version [e.g. 22]

**Additional context**
Add any other context about the problem here.