Will people who sign mobile phone contracts in Singapore be blacklisted? Does ica have anything to do with telecommunications companies? I signed four books and went straight back to China.

This is not just a breach of contract. If it is malicious, it is already fraud.

If the telecom company doesn't sue you, nothing will happen. They have nothing to do with ICA.

However, if the telecom company sues you, it is not only blacklisted, but also possible to go to jail.

You can get in touch with the telecom companies in China and Singapore first. Be polite, say you are in a hurry to return to China or something ... ask how to deal with it and how much it will cost. This is the safest way.

Otherwise, you can only come here at the risk of going to jail. It's up to you to decide whether it's worth the risk.