i have an alert from LUMI wallet asking me to back up because there is a major update coming tomorrow and every wallet will be logged out. Just saying, if is your case this might help you to do not loose your money,because i have just been notified 5 days ago.. i think this is no good from LUMI. I am sure that many will loose funds if they dont make their backup.
There are already some lessons to be learned from your post about LUMI:
1) There are too many players (wallets) that are not well-designed for newbies and non-tekkies (moi)
2) It's annoying that there are so many forks & updates that demand near constant attention, NOT GOOD
3) Read reviews here and consider avoiding cryptos that fork, and wallets that update too much
4) Consider providers that have been serving people well for a long time
5) Take some profits along the way, sell some BTC when it spikes, that way you cannot lose it all
The above thoughts just off the top of my head.