iPad Air's screen flexing in one place

We, just users like you, cannot judge/diagnose that issue remotely, sorry.

Since your iPad is brand new, and still covered by warranty, I suggest that you make an appointment (*) and have your device inspected at an Apple Store or AASP (Apple Authorized Service Provider) among this list:--> Apple – Location Selector. After checking it out, they'll give you all the available options.

Regards

Giulio

(*) You can do it:

• Online:--> Genius Bar Reservation and Apple Support Options - Apple;
• Contacting a local Apple Store or AASP among the list provided above;
• Using the "Apple Store" app, available and downloadable from AppStore.

If you have purchased directly from Apple, you a 14-day unconditional period within which to return your iPad for exchange for a new iPad or refund. If you have any concerns at all, you would be well advised to make use of the opportunity whilst it remains available to you.

Upon expiry of the 14-days returns period, Apple’s warranty terms reserve the right to exchange the iPad for a reconditioned (i.e., not new) iPad.

If you purchased the Pencil and AirPods as individual items, in addition to the iPad on the same order, then you can return the iPad for exchange or refund in isolation.

If the AirPods were included as a promotional item, you will need to establish with Apple how the exchange will be handled. As you will be speaking with Apple, either in store or with Apple Support, you only have to ask the question.

If you have access to a physical Apple Store, providing that you have your proof of purchase, the exchange (or refund) process should be painless. Take the packaging and iPad accessories with your - and, just in case, your AirPods.

Consider that if your [relatively expensive] iPad has a defect, your priority really should be to focus on getting the issue resolved. Your AirPods are of secondary importance.