How do friends in Taiwan Province Province send short messages to the mainland? Add area code?

You have to add 00886, and you have to open international roaming. Even so, you can't get much. I've tried many times, but

The short message card of Taiwan Province saves this trouble, and you don't need to add 00886, just enter the mobile phone number directly. Taobao is still patted.

Sell. Their platforms directly cooperate with Chunghwa Telecom in Taiwan Province, Taiwan Province Mobile and China Telecom in Chinese mainland. You can find the short message card of Taiwan Province Provincial Bank on Taobao. Pjy2 1