Not able to asd my characters to a campaign

Hi there!

I'm having a bit of a problem.

When I create a new campaign, everything goes fine. But when I go to add my own character it gives me this message:

Error: React.Children.only expected to receive a single React element child.

I hit Retry like it asks me and gives me thus message:

Error: Cannot read properties of null (reading 'get')

If there is any way you can fix this or if it's something I have to do on my end, I'd appreciate some help.

Thank you so, so much!