gallery link in album changed

Hello everybody!
In this link you can see my pictures, I put all my galleries together in one album which is shown here: https://www.1thc.net/#/fotos/
First everything worked well but all of a sudden you are not able to access any particular gallery and this errormessage shows up: https://www.1thc.net/#/?album=1&gallery=12
The right link you should find the pictures in is: https://www.1thc.net/#/fotos/?album=1&gallery=12
How can this link change without any editing and more important how can I put the galleries to the right links again?
It would be great if anybody can help me! Thank you!

https://www.ads-software.com/extend/plugins/nextgen-gallery/