Does sometimes it work and sometimes not, may be a ram problem?
Try to close all other running applications when you use Garmin-
Garmin abandoned Mobile XT on phones and it's not releasing new versions since a long time, probably new maps on some phones give problems , or your detailed map has problems.
Try last version
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edit : discovered your problem , now I can see your pics
At night Garmin XT is blue and dark, at day is white, I guess your basemap works ,
your last pic shows your detailed map, basemap isnt visible at 80mt scale.
Maps colors can change in night vision too