Forms :: Not Saving - Validation On Age Doesn't Work?

im now doin' my currently program, actually they requesting for an update. I added birth date column in the module,they asked to the request to put a validation on date, such as:

a. under age
b. :txt_ph_birthdate > SYSDATE
c. if :txt_plan_type = 212 then
17 yrs, 5 mos and 29 days and 40 yrs, 5 mos and 29 day - as validation
d. if :txt_plan_type = 214 then
40 yrs and 6 mos and 55 yrs, 5 mos and 29 days - as validation
e. if :txt_plan_type = 215 then
17 yrs, 5 mos and 29 days and above - as validation

they also instructed me to put the validations in birth date after the column of birthdate, which is the :txt_plan_type(list_item) and i put it in TRIGGER (when-validate-item)after i did the codes and compile it., theres no message for error but i think its not working..it working. i already updates also the insert and the other trigger and procedure, i just add the plan type on it.

i havent edit the save button because the as i read the codes the it just call the procedure that i edit.when i run the program and after i encode the data..and when i press the save button, nothing happens or any confirmation.in addition, why is it that my validation on age doesnt work?

heres the

declare
n_months_between NUMBER;
d_same_day_occur DATE;
n_years NUMBER;
n_months NUMBER;

[code]...