I've not seen any tab or chords of this song, so I decided to make a chords. Hope you guys enjoy! 
Chords used: A,Bm,D,F#,G
DAG I didn't mean to let you down
A You have to believe it
DAG I don't know what went through my mind
A But now I can see
 
G That I waited too long
BmA To tell you how much it matters
A Just to be right here with you
GBmA But I couldn't think of anything better
AG I should have told you so
 
D Baby open your heart
BmG Won't you give me a second chance
A And i'll be here forever
D Open your heart
BmG Let me show you how much I care
F#BmA And I will make you understand
G If you open your heart
ADA To love me once again
 
DAG I'll try to make it up to you
A I want you to know
DAG Baby I swear that I'll be true
A And never let go
G If I waited too long
BmA To tell you how much it matters
A Just to be right here with you
GBmA But I couldn't think of anything better
AG I should have told you so
 
D Baby open your heart
BmG Won't you give me a second chance
A And i'll be here forever
D Open your heart
BmG Let me show you how much I care
F#BmA And I will make you understand
G If you open your heart
AG To love me once again
 
BmA We could relive this pain and sorrow
G But we better do it in time
BmA Start over here and save tomorrow
G I wanna make you mine
 
DBmG Open your heart with a chance
A And I'll be here forever
DBmG Open your heart and I'll care
F#Bm And I will make you understand
A Oh baby,
G If you open your heart
A To love me once again
 
D Baby open your heart
BmG Won't you give me a second chance
A And i'll be here forever
D Open your heart
BmG Let me show you how much I care
F#BmA And I will make you understand
G If you open your heart
AD