/e/ on Samsung Galaxy S8 can't reboot into TWRP

Hi @thomasp,
Welcome to this forum,

This is the Samsung Recovery, it looks like it failed to replace it by TWRP,

What is the model of your device ?
I am afraid it is a special model witch is not compatible,
( it is manufactured specially for an US carrier )
even the SM-G950U is not supported by the codename because of his snapdragon chipset.
Only global/international exynos models are compatible with /e/
please read this :