* FPC version?
* Lazarus version?
When the compiler gives "Cannot find A used by B", Lazarus checks what pas/pp/ppu files are in the search path, and if there is a ppu file it inserts "incompatible ppu=filename, package".
FPC cannot use this ppu for one of these reasons:
* it was compiled with another FPC version;
* it was compiled with (depends on) some other ppu files that are not in the search path;
* you misconfigured some search path(s).
Without knowing how you installed FPC + Lazarus, I'd be tempted to delete both and start again. See the Wiki
macOS: Uninstalling Lazarus and Free Pascal.