Dear Han,
Something wrong in SMS packet. To find a cause, it’s needed to learn SIM808 documentation and make a research. Such work is not included in support.
I recommend to use Telegram to send notifications. Or use special REST web services.
Dear Mr.Mikhail.
Thank You for your repply.
Modem Siemens C35 is difficult to get it in my country. Huawei likes E173x is popular. Dcom USB 3g Huawei is connecting to test. Using this modem to send SMS on computer it works perfectly. Testing to send SMS via Rapid Scada It not worked. Fault is the same. https://ibb.co/xJwrKgr https://ibb.co/LvpKqqH
Where is wrong?
Thank You again.
Han Hoang