If you are going to make a good-natured joke, you can choose an excuse that is reasonable and will not cause too much worry, such as: 1. **Travel plans**: Tell them that you have decided to travel to a remote place, such as an island or mountainous area with no signal, and you may not be able to contact them during this period. 2. **Study/work project**: Mention that you have a very intense study or work project that requires full concentration, such as attending a closed seminar or training class. 3. **Digital detox**: Say that you want to try a digital detox for a period of time, reduce your dependence on mobile phones and the Internet, and focus on self-improvement. 4. **Family affairs**: Say that you need to go back to your hometown to deal with some family affairs, which may take some time and energy. No matter which excuse you choose, it is important to make sure that your friends know that it is just a joke and it will not cause them trouble or worry. You can then reveal the truth at the right time so that everyone can smile.