...

I'm sure they will get back to you on the issue. I'm guessing that they will have to void it altogether though, so you may have to buy the bundle again.

From what I've heard they usually refund for that reason without any hassle.
Not sure if they have to refund the whole order or if they can correct it to the amount you intended to pay so if you just wanted T1 you might wanna buy that again to avoid the Bundle ending before they get back to you.
I would wait another few days or maybe a week and then try sending another email.

never had any issues with a re-fund ... tho 5 days and no response seems a bit to much.

Did u check your spam folder and stuff , and the ticket itself on humble ?

Well, they are probably not working on Saturday and Sunday. And there's still 9 days left of the bundle, so probably they'll contact you somewhere in the next week. If you haven't claimed any keys from bundle, the refunding shouldn't be a problem. If you have, then I don't know, they could revoke all the keys or something? :P

My issue wasn't with refund, but it took over a week, solved nicely so not that much to complain about except you need lots of patience.