Oracle database complains about Unable to extend SYSAUX tablespace, despite it being 15% full

hi,

Anyone know why I would be getting these errors?

OT1QA91P(3):Unified Audit record write to audit trail table failed due to ORA-30032. Writing the record to OS spillover file.

OT1QA91P(3):    ORA-01688: unable to extend table AUDSYS.AUD$UNIFIED partition SYS_P28100 by 1024 in tablespace SYSAUX

I have Oracle 19c, 19.4.0.0. RAC database on Oracle Linux 7.9

I used below query to confirm my SYSAUX is 15% full only.

set linesize 1000

select a.tablespace_name,

a.bytes_alloc/(1024*1024) "TOTAL ALLOC (MB)",

a.physical_bytes/(1024*1024) "TOTAL PHYS ALLOC (MB)",

nvl(b.tot_used,0)/(1024*1024) "USED (MB)",

(nvl(b.tot_used,0)/a.bytes_alloc)*100 "% USED"