Edit: yes I know it's a big fail holding big amounts on online wallets, the current situation is definitely a lesson to me.
It's great that you realized this earlier. I must tell you that Blockchain.com support is very close, it seems that they hire people to be in support without any knowledge of the most common customer issues, they take a long time to resolve any customer issue. I particularly stopped using Blockchain.com because it took 30 days to get my 2FA by sms, they were terrible days I had at that time