Hello, dear marciosantosbrsp
Please provide us with login, unit ID and screenshot of the device configuration (SMS commands and device’s answers) and link to this topic to firstname.lastname@example.org, then we will try to check and help.
Unfortunately, due to the huge number of Chinese devices, faulty trackers may come across. Therefore, if the reason is in the device itself, most likely we will not be able to help you.
But anyway, write to us by email, we will check the device on our side.