According to my Innokin t22 pro users guide, I should connect the USB C type cable to the mains with a 5v 2 amp adaptor.
So I used something off the shelf like this:
https://www.amazon.co.uk/Charger-BOLWEO-Android-Supply-Compatible/dp/B07T3LPGMP/ref=asc_df_B07T3LPGMP/?tag=googshopuk-21&linkCode=df0&hvadid=344254939619&hvpos=&hvnetw=g&hvrand=17594211745195788901&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9046517&hvtargid=pla-783210301656&psc=1
Why then do I find advice on some websites not to connect to the wall, but to use a computer usb inlet etc. and charge more slowly.