My Order Attribute relations don't work, how can I check if everything is configured correctly?
Firstly, check which attribute is used as a parent attribute in the relation. The Order Attributes relations could be created only for parent attributes with the following types: Dropdown, Radio Button, Checkbox Group.
Secondly, please, make sure the attributes in question are set within the same Checkout Step:

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Already Done in Q2'22
Brand-new extensions Google Page Speed Optimizer Powered by SpeedSize™ is a synergy of Amasty Google Page Speed Optimizer and SpeedSize, which will help you greatly increase the site performance due to code structure compression and neuroscience media
What to expect in Q2'22
Amasty always strives to deliver new functionality in accordance with the most popular customers’ requests and e-commerce trends. In this article, we'll share our plans on new extensions, improvements, fixes, and other releases the team intends to be
March'22 results
New Solutions In March, the team presented two new suites that combine features of top Amasty extensions and are attractive price-wise: Must-Haves Suite. Don't know how to grow your business or what to start with? Get our must-have set of features for
February'22 results
Time to check the results of February! It's been a tough end to the month, but let's digress a bit and check out what the team has done. Extensions updates. Besides technical fixes, February was rich in new features and improvements: Jet
January'22 results
Can't help but start with the biggest news of the past month: Amasty switched to Product Subscriptions. It means that all extensions can now be acquired by subscription only. The initially purchased code of the module is still available in the customer