Trying to sign in after dormant for a year.....

So decided to turn on mu PS3 after a year of not using. It has internet just fine and installed all updated just fine.
Would not let me sign in, so I used my personal PC and changed my password. I can get into SEN just fine on my PC, but failed several times using updated password on PS3. Not sure why??? However I did read that the router which I'm wired into could have portal issues....what do I do??
Already unplugged router/modem for 20 seconds and tried...nada.
Please help.