SQLite In Clause not working in trigger

i have two tables Table1 and Table2. Table1 have columns ID,stringIDs and Table2 Columns ID,data

i have created a trigger to delete rows based on table1. it doesn't works if comma Seperated stringIDs are more than one. it works if stringIDs is only single value

create trigger tgTriggerName after delete
on Table1
begin
delete from Table2 where ID in (old.stringIDs);
end