If you're shown the following message at the checkout:
"Unfortunately there are no available Klarna Payment options, please choose another payment method"
It means that you didn't pass Klarna's soft check. This is a standard procedure done by an algorithm that scores you within seconds and determines whether you are eligible to pay with Klarna at this time or not.
If you require further assistance, please contact Klarna’s Customer Service via Live Chat by logging into the Klarna app/account or call Klarna at UK - (+44) 080 818 93333 (free phone) between Mon-Sat from 9 AM to 6 PM
USA - (+1) 844-KLARNA1 (844-552-7621) open 24/7 Ireland - (+353) 01 264 7920 Mo – Fr 8 am – 5 pm
Check how to increase your chance of being accepted for payment with Klarna here: https://www.klarna.com/uk/customer-service/can-i-increase-chances-accepted