It sounds like you are experiencing chronic rhinitis, which can be triggered by temperature changes when washing your face. To relieve your symptoms, a daily corticosteroid nasal spray (such as fluticasone or mometasone) is highly effective for both the sneezing and nasal blockage. Additionally, a non-drowsy oral antihistamine (like cetirizine or loratadine) can help control the sneezing fits. Using a saline nasal spray before these medications can also help clear your nasal passages. These options are safe and widely used, but please consult a doctor for a proper diagnosis and a personalized treatment plan.