A client error (SignatureDoesNotMatch) occurred when calling the UploadServerCertificate operation

Trying to install a multi-domain ssl certificate through AWSCLI using OpenSSL, it's a Comodo PositiveSSL Multidomain certificate.

I followed all the instructions on aws tutorials, and the web. I spent about 2 hours with Comodo tech support making sure I have proper files etc, re-issuing certs, etc., and still no luck.

I keep getting this error when I try to upload using the command shown here and here and there isn't much info on this error online.

A client error (SignatureDoesNotMatch) occurred when calling the UploadServerCertificate operation: Signature not yet current: 20150704T040234Z is still later than 20150704T032257Z (20150704T030757Z + 15 min.)

Anyone know why this is happening?