Notification Sound but no message

[bevstan]

Model: ZE553KL(Zoom)
RAM: 4GB
Firmware/App Version: OPR1.170623.026.WW_user_80.30.76.74_20190319
Location: Auckland, New Zealand
Frequency of Occurrence: Daily
Rooted: Yes
App Name: Messages, Gmail
Description: Notification sound sounds, but there is no SMS message or Gmail message. This can happen several times a day.

[ServiceH_ASUS]

Hi bevstan We are sorry to hear that you are having this issue. Do you refer in locked screen or when phone in used? Do you encounter the problem when using other apps? Please help to confirm,thank you. If your phone already rooted, it won't within the range of our after-sales service.