Lingots not showing up is kind of strange.
I mainly use the app for practice and the clubs option is nice too but for some reason, after getting lingots from the treasure chest they show up and then immediately disappear from the lingot store when I look at it. I have over a thousand so three being gone doesn't make me lose any sleep. :-) But, I still find it kind of fun to see how many lingots a week I can get. It's kind of a measuring device for how many Welsh skills I do and even though I don't care about the gamification so much, tapping the chests is kind of fun. :)
Done! Thanks for reminding me. I actually forgot to do this earlier.
I've noticed that when I go to the store to check at first it shows double the amount I won, e.g. I've won 3 and it shows +6, and then removes those extra 3 and shows the amount it should normally be. Perhaps it's the same with you?