I totally feel you here man
my boyfriend lives in japan and we have a 8/9 hr time difference (depending when our clocks go back or forward) it is always hard finding time to call sksk
he works very hard and can sometimes not message me for a few days but I always try to send motivational messages (even if he sees it after work) what I recommend is sending gifts! I sent him a gift for his birthday (a small present of Irish snacks) and he enjoyed it! Even though your not there physically sending a gift can surprisingly make your bond stronger uwu!
These may be region locked since I have jp Spotify
but this is my own playlist with over 800+ songs including artists such as smileberry,an cafe,synk;yet,vistlip and a lot more