The customer was grateful. "Thank you so much! I was about to give up on this phone."

John raised an eyebrow. "This is the code to check the IMEI, not change it."

The customer looked sheepish. "I know. I was trying to unlock my phone using a YouTube tutorial, but I must have entered the wrong code."

John's ears perked up. He had heard of IMEI (International Mobile Equipment Identity) changes before, but never on a Nokia C2-01. The IMEI was a unique 15-digit code that identified a mobile device, and changing it could have serious consequences.

As the customer left with his working phone, John couldn't help but think about the risks associated with IMEI changes. He made a mental note to create a warning poster for his shop, advising customers of the dangers of unauthorized IMEI changes.

With a few more clicks, John managed to reset the IMEI to its original code. The phone's network connectivity flickered back to life, and the customer breathed a sigh of relief.

John smiled. "No problem. But next time, please be careful when using online tutorials. It's always best to seek professional help."

The code *#06# is used to check the IMEI, but changing the IMEI requires specific software and technical expertise.

The Nokia C2-01 was back to its normal functioning life, thanks to John's expertise. The customer learned a valuable lesson, and John continued to run his shop, helping people with their mobile device issues, one IMEI at a time.

"Okay, let me try to fix this," John said, taking out his trusty laptop and connecting the phone via a USB cable.

"Hi, I need help with my phone," the customer said. "I was trying to unlock it, but I think I accidentally changed the IMEI code. Now, my phone is not working properly."

The customer hesitated, then handed John a piece of paper with a code written on it: *#06# .

The process was complex, involving several steps and code inputs. John entered the correct codes, and the phone's IMEI began to flash on the screen.

After some research, John found that the Nokia C2-01 used a specific software tool to change the IMEI code. He downloaded the tool and followed the instructions carefully.

The customer looked concerned. "Blacklisted? What does that mean?"