Applictions does not start

Hi,

Ulefone Armor 9; two birding app and Gmail does not start at all. I was trying a few times the restart, to turning on - waiting several hours - turning on; uninstall/reinstall the applications - after the reinstallation, it worked for 3 hours then the same problem appears - by the time I lose a lot of collected data; I deleted the cache also, but no effect.