I have the MPP and have used the S8+ , S10+ and now the S20+ without any major problems other than a few disconnects. Have you tried to uninstall and reinstall the App ?
When I fly around water I always have this on my Mavic Home It could save you from getting wet yourself . If you do a search you can find it on a few different web sites.Don't know why the link says home but it works .
I have a nice bright strobe on my Mavic and it helps a lot seeing it farther out ,give it a try .You can find them at Carolina Drones ,Ebay for under 30 bucks .