Voiding all warranty one can open the phone and change the battery. Also, replace the screen. There are websites with step-by-step instructions on most phones, and this one is just a matter of time.
The Problem is that Nothing charges unreasonable amounts to fix it themselves. More than the phone costs. Obviously to avoid having to do repairs. And this is ok, their choice. But what is not is not ok, is to then NOT sell and ship out the spare parts to customers for a reasonable amount. These phones sold record amounts. There is no case/protector available in UK. Environmental nightmare unfolding? Why can Nothing just sell a screen for 24 pounds and ship it at customers expense? I guess we just have to wait until it pops up on 3rd third-party web store while we contemplate if profits are put above sustainability in this case.