cannot filter the same order no inside the same table

Hi All,

i am having issue here.

i have one page which contain lots of data, an i need to filter inside the table which is not the same as the previos one

for exmaple
Entry no. Order no Desc
1 123 abc
2 123 def
3 234 xxx
4 234 yyy

my case is that i need to change 'xxx' into 'abc'.
i have trigger something and declare a record variable (t1) of the same table that will go like this

t1.reset;
t1.setfilter("order no",'<>%1'"order no")
if t1.findfirst then
mofidy the desc

but my order no will not go to 234, it sticks to 123. can you please help me what is missing ?

thanks,