GPSMAP H1Plus problems synchronisatie bleutooth iPhone messenger App

Hi ,

I have a lot of trouble with sending SMS messages from GPSMAP H1plus through iPhone Garmin messenger into the internet. 
After trying the Tips the connection is and stays very in-stable. 
I need very often a reset of the hardware to send a message on its way. 

if there is no Bluetooth connection the GPSMAP H1Plus sends the message very fast over WIFI but if I connect Bluetooth the connection stops our is very slow. 

every solution Garmin offers doesn’t work. Is there a better way to connect or solving this. 
this is a very annoying problem