/spawnpoint command don't work

When using /spawnpoint @a x y z,
and kill myself, got respawned at ONLY world spawn chunks, and got
Your home bed was missing or obstructed

Also
/execute at @a if block ~ ~-1 ~ minecraft:gold_block run spawnpoint @p ~ ~ ~
don't work, but work with
/execute at @a if block ~ ~-1 ~ minecraft:gold_block run say @a abcd