INSERT INTO statement with select
use nextvalue(idstackacos_find_the_right_sequence_name ) instead of 

OLD: 

SELECT 'notyetindbisforsureunique', '2018-09-18 14:34:57', '2018-09-18 14:34:57'


NEW: 

SELECT nextvalue(idstackacos_find_the_right_sequence_name) , '2018-09-18 14:34:57', '2018-09-18 14:34:57'


If it's not working please copy here the definition of the table and of the sequence.