There are a few different reasons why orders could fail in Paypal, including customers having insufficient funds, entering the wrong card details, an error on Paypal's system, etc.
However, there are a few things you can do to ensure your setup is not the reason orders are failing.
Firstly, you want to make sure you've followed all the steps in our Paypal setup guide. This contains the basics of getting things up and running, and if you've not followed these steps, this is the first thing you should address.
Then you want to check that you're not blocking encrypted website payments, as this can stop payments going through. This can be checked in Paypal, by clicking the seetings cog, then
Account Settings > Website Payments > Website Preferences - click update, (or click here) then scroll down and make sure "Block Encrypted Website Payments" is set to 'Off'.
Next you'll want to make sure you're automatically accepting currency conversions, otherwise the order will sit on 'Pending' until you manually approve the transaction. This is far from ideal if you're making regular sales. To do this, click here to go to your payment settings, change the first setting “Allow payments sent to me in a currency I do not hold:” to “Yes, accept and convert them to (your currency)”.
If all of this is correct and you're still seeing failed orders (assuming the customer has contacted you and you know the error is not down to something they're doing wrong), you can try creating a direct purchase link, which will take them straight to checkout. This is done by sharing your cart.
If all of this does not result in a successful sale, feel free to contact us and we'll look into this for you. You may also need to contact Paypal as there may be something going wrong on their system that cannot be resolved by you, the customer, or Airbit.