Ouch, looks like corruption on the data file.
Anyway you can check which snapshots are using this broken file by:
restic find --pack 28802ae5cf4bea45a0acdda16d399eb6a429299b51835a203c151d63fb910734
And forget all relevant snapshots (if this is acceptable), and then prune.
You might want to run a memtest or FS health check also, considering this looks very fishy.
Or someone else can recommend something better, maybe recover command somehow skips checking hashes etc…