Why do df/used% and lvs/data% (thin provisioning) not match?

Issue

• A small percentage is shown in df/Used%, but that associated lvs/Data% almost full.
• How to sync up between df/Used% and lvs/Data%?
• There is a significant discrepancy between df/Used% and lvs/Data% (thin provisioning), as shown below:

# df -h /home
Filesystem                Size   Used  Avail Use% Mounted on
/dev/mapper/rootvg-home   1014M  102M  913M   11% /home   <===11% Use%  from df for filesystem /home

# lvs | grep home
  LV              VG        Attr         LSize   Pool   Origin  Data%  Meta%  Move Log Cpy%Sync Convert
  home            rootvg    Vwi-aotz--   1.00g    tpool0        99.99   <====but the Data% from lvs is 99.99