So, this question pops up quite regularly. Here are some things you can check:
- Does the port still exist?
Packages are built from ports, so check an up to date ports tree, cgit ports, or Freshports. Ports do get deprecated (older, EoL, versions for example). Or it might be broken beyond repair. No port, no package, it's that simple. - Port got renamed.
Doesn't happen very often but does happen. The MOVED file in the ports tree will tell you what the new name is. - Port exists but package(s) for it are missing.
Sometimes ports, or one or more of its dependencies, fail to build. With 32000+ ports this is bound to happen. It happens to some ports more often than others. Typically complex ports with lots of dependencies can suffer from this. Check Portsfallout and/or pkg-status.