Heroku error when trying to submit job posting

[Moini]

Hi,

I've been wanting to submit a design job for this year's International Software Freedom Day, but unfortunately, when I submit my data, I get:

This is the content I submitted (in case it's relevant):

Software Freedom Day

https://www.softwarefreedomday.org/

Graphic assets for the 20th edition of International Software Freedom Day

Graphic Design

SFD needs your help with setting up some cool artwork for the 2023 edition! Event organizers around the world will make use of your work for their SFD event on September 17, 2023.

For this year's edition, which is also the SFD's 20th anniversary, we're looking for one or multiple persons who can help creating various assets for the event:

Based upon the existing artwork,

*  an OBS template for people who want to stream their SFD event
*  a banner that includes that it's our 20th
*  some fun social media infographics or memes
*  your own ideas: flyers, goodies, stickers, whatever you enjoy making a template for (we don't know whether we will have any sponsors this year, so materials may be for self-printing by independent event organizers)

To determine details, such as file sizes / formats, and for sharing your own suggestions, please join the SFD organizer team in our matrix channel! 

If you're not familiar with Matrix yet, please say hi on our Mailing list so we can help you to get all set up.

Jurgen Gaeremyn: @jurgen_g:matrix.org (Matrix)

Maren Hachmann: @moini:tchncs.de (Matrix)

Our Matrix channel (please say hi here): #SoftwareFreedomDay:matrix.org
Our Wiki (with links to all the existing artwork): https://wiki.softwarefreedomday.org/FrontPage
Our Mailing list ([email protected]): https://lists.mailman3.com/postorius/lists/sfd-discuss.mailman3.com/

event assets, banner, social media graphics