Running a test fails with "ORA-00001: unique constraint (UT.UT_OUTPUT_BUFFER_TMP_PK) violated"

utPLSQL v3.1.12.3589
Oracle DB 19.17
SQLDeveloper; with DBMS Output enabled.

BEGIN ut.run('my_test'); END;
Error report -
ORA-00001: unique constraint (UT.UT_OUTPUT_BUFFER_TMP_PK) violated
ORA-06512: at "UT.UT_OUTPUT_TABLE_BUFFER", line 29
ORA-06512: at "UT.UT_OUTPUT_REPORTER_BASE", line 85
ORA-06512: at "UT.UT_REPORTER_BASE", line 213
ORA-06512: at "UT.UT_EVENT_MANAGER", line 70
ORA-06512: at "UT.UT_EVENT_MANAGER", line 80
ORA-06512: at "UT.UT_RUNNER", line 26
ORA-06512: at "UT.UT_RUNNER", line 149
ORA-06502: PL/SQL: numeric or value error: character string buffer too small
ORA-06512: at "UT.UT_UTILS", line 470
ORA-06512: at "UT.UT_OUTPUT_TABLE_BUFFER", line 40
ORA-06512: at "UT.UT_OUTPUT_REPORTER_BASE", line 53
ORA-06512: at "UT.UT_DOCUMENTATION_REPORTER", line 53
ORA-06512: at "UT.UT_CONSOLE_REPORTER_BASE", line 26
ORA-06512: at "UT.UT_DOCUMENTATION_REPORTER", line 120
ORA-06512: at "UT.UT_DOCUMENTATION_REPORTER", line 137
ORA-06512: at "UT.UT_DOCUMENTATION_REPORTER", line 150
ORA-06512: at "UT.UT_DOCUMENTATION_REPORTER", line 163
ORA-06512: at "UT.UT_DOCUMENTATION_REPORTER", line 203
ORA-06512: at "UT.UT_REPORTER_BASE", line 193
ORA-06512: at "UT.UT_EVENT_MANAGER", line 70
ORA-06512: at "UT.UT_EVENT_MANAGER", line 80
ORA-06512: at "UT.UT_RUN", line 66
ORA-06512: at "UT.UT_SUITE_ITEM", line 50
ORA-06512: at "UT.UT_RUNNER", line 144
ORA-06512: at "UT.UT", line 139
ORA-06512: at "UT.UT", line 493
ORA-06512: at "UT.UT", line 628
ORA-06512: at line 1

1. 00000 - "unique constraint (%s.%s) violated"
   *Cause: An UPDATE or INSERT statement attempted to insert a duplicate key.
   For Trusted Oracle configured in DBMS MAC mode, you may see
   this message if a duplicate entry exists at a different level.
   *Action: Either remove the unique restriction or do not insert the key.