The previous owner of the house repointed over the damp proof membrane and the mortar directly above and below the DPM was very soft. I raked out the joint with a view to repointing properly but unfortunately some of the DPM has broken off with the old mortar. Should I repoint up to the edge of the DPM and leave a gap in the joint at the front or is there some way I can trim some DPM into the gap. Cheers.