Your version is outdated,
you must use one of the latest, currently
e-2.8-t-20250219470165-official-FP3.zip
For a new installation (wiping /data) :
Install /e/OS on a Fairphone FP3/3+ - “FP3”
using :
https://images.ecloud.global/official/FP3/IMG-e-2.8-t-20250219470165-official-FP3.zip
(you need ti be in fastboot mode and run the included flash_all.script)
. . . . . . . . . . . . . .
For update or upgrade (preserving /data) :
Dirty upgrade to /e/OS-T is possible ! (But not for all devices) - #56 by piero
using this file :
https://ota.ecloud.global/official/FP3/e-2.8-t-20250219470165-official-FP3.zip
not the IMG-e-2.8-t-20250219470165-official-FP3.zip one