Complex sentence: In some jurisdictions, including China, Israel, and Singapore, SIM locking is illegal, but in other countries, carriers do not provide unlocking codes, or oblige the consumer to pay a fee.
Split into simpler sentences: In some jurisdictions, including China, Israel, and Singapore, SIM locking is outright illegal. But in some other countries, many carriers do not provide unlocking codes, and some who do force the consumer to pay a fee.