Every few months or so (120 days max), your UnionBank EON Account will prompt you to change your Transaction Password to keep using their online banking services.
Please take note that your Transaction Password is not your ATM PIN or EON Account password. This is something else. If you keep putting your ATM PIN there it will only result in INVALID TXN PASSWORD request. You also need to remember all the past transaction passwords you used, as you cannot keep using the old ones.
So I hope you do have a record of your previous Transaction Password from 120 days ago.
If you don't remember, then call the Unionbank hotlines to reset your transaction password:
84-186* or (02)841-8600
Domestic Toll Free
Universal Toll Free
But remember to have your EON card with you as they will ask you for the 12 digit code of your EON account, email address (you signed up with the bank account). You will need to wait 2-3 days before you receive the email on resetting your password.