Issue with Heroku

Hi, I’m no hardcore coder but I know enough get around.
Anyway, I have been seeing up my website with Kirby. Before I went with Heroku I have been using and everything worked perfectly. The site also worked perfectly locally.

When that is said, the site itself is working The problem emerges when I log in to the Panel. Logging in goes smoothly, but when I click any link or button inside the Panel I get thrown out and have to log in again. This happens over and over.

Anyone here got a clue?

There was a similar issue here. Maybe that helps you.