I got some problem to share with, I've been testing push mobile notification via AWS-SNS push noti service and it works properly when my app is on foreground or background my notification almost come instant time after publishing but, there are some cases that may bug my app/works.
When my app had been killed from foreground or no interaction with my phone for a while(around minutes), notification that was sent from SNS then to FCM got delay and sometimes It required opening(wake up screen) mobile then notification will show up after that. This was weird and interesting at the same time.
What I have done so far:
I come through fcm doc spec - setting high priority to my noti message then my payload look likes,
{"data":{"payload":{}}, "priority":"high", "android":{"priority":"high"}}
I've set priority key to follow legacy HTTP API and HTTP v1 API already(Yes, I test with both cases) but, the behavior still got an issue
***I tested on Huawei phone, Android 8.0.1
NOTE: For APN, IOS works properly and I am so new to mobile dev so, feel free to suggest anything to me
Thank you in advance.