ᐅ The toilet seat is wobbling back and forth. How can I tighten it securely?

Hi!

I have had a problem for a while now where the toilet seat is becoming increasingly loose. I have already watched videos on how to tighten it again, but in our case, the mounting to the toilet bowl is different from what is shown in the videos. What is the best way to tighten it again?

It concerns the screw on the left in the picture.

Thanks in advance for the help!

What does the fastening look like from below?

Do you mean from behind/under the toilet?

Thanks for the tip, the nut on the other side had come loose... I could have been pulling on it for a long time! Thank you for the advice! Now the cover is tight again.