Not to worry.!! Your problem is probably due to an "uneven" application of
your last coat of varnish. It has happened to me several times.

Another coat will probably cure the problem. But exercise some caution
before the final application. First, lightly sand to remove all traces of
"gloss". Fine sandpaper or 0000 steel wool works for me. Clean, then clean
again..............finally apply a final coat. Be sure to have a strong
light available so that you can clearly see the evenness of the varnish
being applied.

LOL, John