Here are two items from Crewkerne with Postage Due markings, the first from March 1932. The postcard is underfranked with ½d when the correct rate was 1d. The postcard received a "1D / 230" charge mark and a 1d postage due which was cancelled when the charge was collected.
The second item from March 1975 received a framed postage due charge mark with manuscript "1p". Actually the correct postage due should have been 11p as the stamp was an old pre-decimal one.