> For the complete documentation index, see [llms.txt](https://docs.syfu.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.syfu.io/quick-start/activation-code.md).

# 1.1 How to Use an Invitation Code

You can register and start using SyFu without an invitation code.

The invitation code is optional. If you are registering for the first time in the app, you can enter it during registration. If you already have a SyFu Card or Marketplace account, you can enter it when you first log in to the app with that account. Once the initial app setup is complete, the invitation code cannot be added or changed.

If you created your account on the web and are logging into the app for the first time, you are eligible for the new referral slot. The purchase deadline and referral period start when you enter the invitation code in the app.

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#### How to enter your invitation code

<figure><img src="https://1134738271-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fvy79mmiJQYM9eyapZ0o1%2Fuploads%2FWff95NSIkJf2ANrHhg2w%2F%E3%82%A2%E3%82%AB%E3%82%A6%E3%83%B3%E3%83%88%E7%99%BB%E9%8C%B2_EN.png?alt=media&amp;token=def2cac7-f749-4392-9eee-e2ab927ad928" alt=""><figcaption></figcaption></figure>

1. Open the SyFu app and select registration or login
2. Enter your email address and request a verification code
3. Enter the six-digit verification code sent to your email
4. Enter your invitation code in the optional invitation code field
5. Check your code, then complete the first-time app setup

If you do not have an invitation code, leave the field blank and continue.

***

#### Before you register

* If you already have an account on the SyFu Card site or Marketplace, you can enter the invitation code when you first log in to the app. Please log in using the email address you used on the web.
* You cannot add or change a code after completing the first-time app setup.
* Please refer to the official campaign and referral program details for benefits and eligibility requirements.

***

#### Frequently Asked Questions (FAQ)

**Can I use SyFu without an invitation code?**

Yes. Entering a code is optional. You can register an account and start using SyFu without one.

**Can I use an invitation code if I already have a web account?**

Yes. If you created an account on the SyFu Card site or Marketplace, you can enter the invitation code when you first log in to the app.

**Can I add a code after I start using the app?**

No. You cannot add or change the invitation code after completing the initial app setup.

**What if I have trouble entering my code?**

Please check that the invitation code has been entered correctly. If the issue persists, please contact us through the support ticket feature on our official [Discord](https://discord.gg/kPMczw5rfe).

***

#### Next step

After registering your account, create your SyFu Wallet.

Continue to “Create your SyFu Wallet” in [0.2 Getting Started with SyFu｜App Setup and Initial Settings](/introduction/syfu-in-3-minutes.md).