I have Messenger on my Samsung S6 and also on my computer. The area I live in has poor reception. If I send a message from the computer it goes instantly but if I use the phone it sometimes takes a very long time to go. I have my phone set to use WIFI calling when mobile network is not available. If I try to send a photo from my phone it can take 20 minutes to send if it sends at all. Is the WIFI calling feature just for calls or is it supposed to work with Messenger also.