Conclusion:
I am not 100% sure who is to blame for this issue,
but I know that we should NEVER use any online wallet,
no matter how safe they claim it is.
Unfortunately, you are late to find this out and it comes from your bad experience, When I was just starting out I've read a lot of users losing their Bitcoin because it was stored in an online wallet, that is why online wallet and a phone wallet is the least of my priority among all wallets,
Ledger wallet is always the best choice but if you still cannot afford a desktop wallet and a strong password is the best option, so far all my coins are safe because I never use an online wallet, people who are new here should always secure their by picking the best option.