LVM volume has a data percent bigger than 100%

One of my LVM volume is shown to have 372.6% data. How could this happen? Note the volume have been re-sized down from a bigger size, but the file system seems working fine. It actually impacts the pool's free space availability. Basically, even the file system and LVN have be resized to a smaller size, the space is not freed.

The question is, how to make any unused space available for use?

# lvs
  LV        VG   Attr       LSize    Pool Origin Data%  Move Log Cpy%Sync Convert
  lv1       vg1  Vwi-aot---  820.00g tp1         372.60
  lv2       vg1  Vwi-aot--- 1000.00g tp1           1.60

The LVM tree structure looks like this:

# dmsetup ls --tree
vg1-tp1 (253:6)
 └─vg1-tp1-tpool (253:5)
    ├─vg1-tp1_tmeta (253:1)
    │  └─ (147:1)
    ├─vg1-tp1_tierdata_2 (253:4)
    │  └─ (147:1)
    ├─vg1-tp1_tierdata_1 (253:3)
    └─vg1-tp1_tierdata_0 (253:2)
ce_cachedev2 (253:11)
 └─cachedev2 (253:10)
    └─vg1-lv2 (253:9)
       └─vg1-tp1-tpool (253:5)
          ├─vg1-tp1_tmeta (253:1)
          │  └─ (147:1)
          ├─vg1-tp1_tierdata_2 (253:4)
          │  └─ (147:1)
          ├─vg1-tp1_tierdata_1 (253:3)
          └─vg1-tp1_tierdata_0 (253:2)
ce_cachedev1 (253:8)
 └─cachedev1 (253:0)
    └─vg1-lv1 (253:7)
       └─vg1-tp1-tpool (253:5)
          ├─vg1-tp1_tmeta (253:1)
          │  └─ (147:1)
          ├─vg1-tp1_tierdata_2 (253:4)
          │  └─ (147:1)
          ├─vg1-tp1_tierdata_1 (253:3)
          └─vg1-tp1_tierdata_0 (253:2)