Thank you for the invitation, but I won’t be able to attend.
I appreciate the invite, but I have to decline.
I’m sorry, but I can’t make it.
Thank you for thinking of me, but I must pass.
I’m unable to join this time.
I have a prior commitment and can’t attend.
I won’t be able to be there, but I appreciate the invite.
Please count me out for this one.
I’m going to have to decline.
Thank you, but I’m not available.