Soot regeneration continuous problem

[60bend]

Hi I have a monthly problem with regenerate soot message ,I have tried the high revs 20 mile drive but the message turns to injector problem message during drive ,and then goes into limp mode,I have had this car connected to a laptop to clear soot filter at the end of December , in January we drove to the coast for new year ,so the car has had a reasonable run ,but the message is back just 1 month later ,surely this can't be normal it makes the car not fit for purpose ! .Does anybody have any ideas please ?