I havn't updated my phone for years

Hi @lhp22 welcome to this forum.

What is the version actually installed ? [HOWTO] Give complete /e/OS version info easily for support, answers, comparison etc
Is your bootloader open or locked ?

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… by the system updater, so it could be a dev version

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Backup as much as possible…(in case)

  • Orthodoxe way is to follow Install /e/OS on a Fairphone FP3/3+ - “FP3”, with 2 notable differences : don’t unlock or relock your bootloader, and DON’T WIPE OR FORMAT ANYTHING ! during the process,

  • but as “T” build generation include updated firmware parts, you should simply download this “recovery compatible” e-2.2-t-20240717417775-dev-FP3.zip (not the “fastboot compatible” IMG-e-2.2-t-20240717417775-dev-FP3.zip),
    Then, reboot to recovery and apply the update (upgrade in fact)