Cyclone 10 Low Latency 10Gbase-R core has a problem to fit the serial tx/rx signals

Hallo,

I'm using the low latency 10GBase-R core on a Cyclone 10.

When I started the project the compiler worked fine.

After a some iterations in my project the compile didn't fit anymore. For the error message see attachment.

I tried to revered all changes but I never got it to work again.

I started again from scratch, but after a while I run into the same issue.

Do you have any idea what could cause such an error message?

regards

Michael