Trying to check out (buy) assets on the asset store, and I know that I have enough money on my card and I know that the info was typed properly, and I get the following error;
“The system failed to charge the order, we could not process your card at this time. Please double check your billing details, try a new credit card, or contact your bank[ERR:107]”
What’s the problem and how can I fix it?
In my case it was because I was on a VPN. You might try from a different ip if possible (mobile hotspot?) . Of course in my case I’d say unity should consider not letting the transaction get to the approved state if it’s just going to be reversed again afterwards 
I am having the same issue. Did you manage to find a fix?
So I am also on a VPN,and I tried to disconnect once from my VPN and still no joy. 4 transactions, all showing on my bank. My bank removed 3 out of 4 of them,but for my first transaction with Unity I was/am not so happy, even if the sale was only 5 bucks…
I’m having the same issue with paypal. Two days ago, I was able to buy a new asset. Trying today, I get the error 107, Very frustrating. I get to the page where you can click credit card or paypal, hit paypal and that’s the end.
The issue is still there. Paypal or not.
Fun thing is: error or not, the purchase completes with success 95% of the times.
I run into this issue when buying 30 or more assets in bulk or paying 300 or more dollars.
If the cart appears as empty after 5 minutes, everything went fine. Just check the individual pages of the asset you purchased.
I asked the support several times now and, well, I simply had to try again. Have also been marked as fraud a few times.
It happens on both stores, old and new. Just wait a bit and try again.
If it doesn’t work with paypal, try with debit/credit cards (or viceversa) after half a hour, or on a totally different time of the day.
As last resort, get in touch with support (2 days waiting, typically).
At least you can ask to investigate on the actual transaction error.
and now 2018 this is still happening 
have the same thing, can not buy with Paypal or with my debit card
Still getting this error in January 2019. Switched to the Old store did the order there - everything worked normally. I guess there is some sort of problem with the new store payment.