You are likely thinking of the Unihertz Jelly 2 (often referred to as the "Jelly 2" or model "228" in some listings). This is a tiny Android smartphone.

: As UScellular and T-Mobile integrate their networks, activation processes have moved to automated digital systems rather than star-codes. Recommended Solutions

If you are trying to activate a small smartphone and it isn't connecting:

Here’s a structured for the issue “228 not working on US Cellular,” suitable for a customer support knowledge base, troubleshooting guide, or product feature description.

: Modern smartphones (4G LTE and 5G) use SIM cards or eSIMs to automatically update network settings and do not require manual programming via *228.

Here is the breakdown of what "228" refers to in the context of US Cellular and how to fix the issue.

If your device is not working on US Cellular, follow these steps based on your situation.