Social Media Linkedin Link wrong

Your software
My Mautic version is: 4.4.3
My PHP version is: 7.4.32
My Database type and version is: 10.5.15-MariaDB

Your problem
My problem is:
I added social media button on a landing page. FB, Instagram are correct and the link works. Only Linkedin is not working. The link looks like this although I entered only the address and username like on the other social media channels.

These errors are showing in the log:

Steps I have tried to fix the problem:
Tried to enter only /in/username without the

Many thanks