iPhone Particle app Particle.variable() Error

I have 3 asset trackers, and am having trouble using Particle app v2.0 on iPhone 10.0.2 reading from cloud the string variables sent by ELECTRON. Usually they read correctly, but today mostly they do not.
Screen below of when it reads ok, and when it shows ‘error’. Firmware source at bottom.

The version of firmware has been working great in the past. Today, awful.

Each tracker has a GPS fix (no red GPS LED).

WHEN IT FAILS…

WHEN IT’S WORKING…

ELECTRON CODE:
String publication_Lat_Lon; // Lat. and Long data from AssetTracker object
String version_PROGRAM_TITLE = PROGRAM_VERSION;

void setup(){

Particle.variable( “Version”, version_PROGRAM_TITLE );
Particle.variable( “g”, publication_Lat_Lon );

}

void loop(){

publication_Lat_Lon = String::format( “%f,%f”, latest_good_latitude, latest_good_longitude );
…}

Could you use something else to check that variable to rule out issues with the app? The CLI, DEV, this page should all be able to do so.

Thanks, Moors7, I will.
Presently, there’s no problem; iOS Particle app is reading all 3 asset trackers ok.