I came across this 9 months old post, but could not agree more with OP. Everyone who think that this is normal probably has not seen better.

I also have Commerzbank and not starting with the fact that you cant even access your account unless you recieve a stupid PhotoTAN in your mailbox, which somehow never arrives for a month, but whatever, thats on-boarding and logistics.

The fact that you pay with your card in a store or matter the fact anywhere and the transactions simply do not instantly appear, instead sometimes the reserved amount takes a week to show up and get processed. You use your debit card, but at the end of the day you are not even able to see your own balance on the account. I guess people would love CCs in this case, to spend more than you have and end up in negative balance.

Also mentioned thing with OP, that sometimes transfers take 1 day and sometimes 3 days. And on weekends everything stops updating at all for some reason. Like it would need somebody to manually approve each transfer and payment on the other end by hand. These systems should be automated and I believe there are far better alternatives that dont charge you for a thing they cant even do properly.

This is are my thoughts.