Because Load inserts data by pages, the tablespace need to be recovered for data consistency.
if the load fails, you have to do load terminate.

Example of a table space state

If you load an input file (staffdata.del) into a table NEWSTAFF, as follows:
update db cfg for sample using logarchmeth1 logretain;
backup db sample;
connect to sample;
create table newstaff like staff;
load from staffdata.del of del insert into newstaff copy no;
connect reset;
and you open another session and issue the following commands,
connect to sample;
list tablespaces;
connect reset;
USERSPACE1 (the default table space for the sample database) is in the Load in Progress state and, after the first commit, the Backup Pending state as well. After the load operation finishes, the LIST TABLESPACES command reveals that USERSPACE1 is now in the Backup Pending state:
Tablespace ID = 2
Name = USERSPACE1
Type = Database managed space
Contents = All permanent data. Large table space.
State = 0x0020
Detailed explanation:
Backup pending

Solved:
Backup the database to clear “Backup pending” state
db2 “backup db nongdb tablespace (USERSPACE1) online to /dev/null without prompting”