Point of order, Tannoy is a brand name, similar to Hoover or Sellotape.
The use of PA system, vacuum cleaner and sticky tape is deemed more appropriate and less brand biased.
Sony Xperia devices:
The NFC detection area is located on the front of the device. Hold your device close to another device or an NFC reader so that the NFC detection areas touch.
Email Chelsea and ask them.
https://www.skysports.com/football/news/11668/12366170/chelsea-to-ask-fans-for-proof-of-vaccination-or-negative-covid-test-ahead-of-mens-and-womens-home-games