mysql - left join - trying to find missing records in 2nd table when there is still similar record fitting match condition -

i have 2 tables

table 1

table 2

i want find missing records in table 2 when:

table 1 :
message type: request send
id: 1

table 2 :
message type: request received
id: 1

table 1 :
message type: response send
id: 1

table 2 :

nothing

now join find missing responses in table 2:

select t1.id  table1 t1  left join table2 t2 on t1.id=t2.id  t2.id null  , t2.messagetype<>'request received'

unfortunately 0 rows. guess because there t2 record matching id filer out messagetype condition. how can solve this?

a simple not exists clause should sufficient:

select *   table1 t1  not exists (select null                      table2 t2                     t2.id = t1.id)

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