Uploading own theme does not work

Hi,

Today i’ve created my own theme, following the steps that the MailPoet website showed me. I used the right extensions, but everytime i try to upload my theme it says: you are using a wrong extension or something like that.

I used .png images and a style.css file along with the right folders. I also compromised the files in a .zip file as requested. I tried everything from changing names to re-compromise the files, but it doesn’t work.

I hope someone can help me with this.

Thank you in advance.

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