Press and hold on the notification. This will give you a few options. I forget what one i clicked on but it brought up the options for the message+ app. Scroll down and turn off background message sync. That did it for me. I have the Pixel2.
Seeing this type of message on your phone is definitely concerning and we can understand wanting to find out why this is happening. When did this first begin? Do you notice any patterns happening around when it appears on your screen? Has there been any new changes to your device?
This happens frequently on my Pixel2 as well. I can almost always replicate it when I am at one certain location. Message+ also seems to be a primary battery drain on my phone, and I don't text a whole lot throughout the day.
I have Pixel 2XL & just solved the same issue. I'm kinda in a hurry so I don't have time to look at all the others solutions. My apologies if someone already gave this same answer. This is also my first time on this forum (or any forum, really) so I don't know all the ins & outs, etiquette, etc. So please forgive me if I am stepping where I don't belong. I too, was looking for a solution for this issue. I started to follow one of the suggestions & some how managed to end up in just the right place. Here is what I did and it worked for me so far.
Open settings, choose Apps & Notifications. Locate and choose Message+. Locate and open App Notifications. In there you should see Background Message Syncing. Turn it off.
Again, if someone already suggested this, I apologize.
Did this ever get resolved? I just started getting this last week after clearing out some cache from a few apps.
I have an MOTO Z. Android 8.0.0
tried this fix, got all the way to the last part and could not find it like you had problems. so i went
Aplicaciones y notificaciones
this fixed the problem and it is no longer on my phone
Long press the notification.
scroll down to 2nd to last option 'background message syncing'
turn that off.
I had the same problem. I was able to hold down on the message and there is an off and on button. Switch to off. It was gone