Although the 50-year-old star personally invited Ryan to the bash earlier this week and he flew from New York to Miami especially for it, he was mortified to discover his name was not on the guest list when he arrived but luckily for Ryan, he got in to the party after a slight delay.
Ryan explained to 'Live With Kelly and Ryan' co-host Kelly Ripa: ''She sent me an invitation and I was like, 'Wow, I got a direct invitation' ... but the catch was, it was in Miami. So I committed, but I didn't read the small print.
''I've known her for a long time. I'm going, I'm getting down there; I'm getting back in time and I'm gonna be there because I got the personal invite.
''I get to the front ... proud, beaming, smiling. And [the guy] has a list and I see there are a bunch of Ryans ... and he says, 'Well, you're not on the list.'
''This is a true story. So I say, 'Clearly, there must be a mistake ... she invited me personally. Can I see the list?' Well, sure enough, there's Ryan T. and Ryan Z., there's no Ryan Seacrest.''
Ryan had hoped that since he and Jennifer are friends and have worked together on 'American Idol' that security would let him in, but he was told to wait while they made a phone call to check if he could come in.
However, he eventually made it inside and ended up sitting at the head table with Jennifer and her fiancé Alex Rodriguez.
Ryan, 44, had to be back in New York early the next morning to tape 'Live With Kelly and Ryan' but admitted sneaking out of the bash before it ended was not easy.
He said: ''I think, 'There's a lot of people, so this is gonna be easy'. I have to leave in the middle of the dinner, but they won't know because there's so many people there. [Sitting with Jennifer] was great, but difficult if you have to leave.
''Then A-Rod gets up and makes the most romantic, sweetest speech to Jen in front of everybody. So, I'm sucked into the romance movie and I don't want to leave.''
The star-studded bash at Gloria and Emilio Estefan's sprawling estate on Star Island in Miami was also attended by DJ Khaled, Fat Joe, Ashanti, and Jennifer's 11-year-old twins Maximillian and Emme.
Jennifer posted on Instagram after the party: ''It's been a birthday to remember. I can truly feel the love from all of you. Yesterday was a dream. I have watched your beautiful birthday videos and I must've cried 20 times. It was just another great reminder of how thankful I am for all the beauty and love I have in my life. Thank you all for being a part of this great feeling! @arod, Benny, @quayaustralia, @prettylittlething and so many more! The party continues tonight!!! (sic).''
Listen to her new song 'I'll See This As A Blessing'.
This article is dedicated to Caroline Flack.
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