My hubby always congested, uses nasal spray nightly despite the directions! Snores very loudly due to sleep apnea, cpap didn't work for him. Advice?

Constant nasal cong. Constant nasal congestion can be due to allergy.What kind of nose spray is he using.If he is using over the conter afrin or neosynephrine that may be real cause of his congestion.He should see a doctor and come off afrin gradually as you get chronic rebound congestion due to it.Sleep apnea always respond to CPAP if he is using it, you should also make an appt with sleep speacialist.First see yr md.
Needs an ENT eval. Before any type of treatment with a mandibular advancement device or other oral appliance he must see an ENT doctor and get off his decongestant nasal sprays. Frequently just improving nasal airflow can improve snoring and airway symptoms. Once he can breath through his nose again then nasal CPAP may be much more successful.
Try a MAD. Ask the md to prescribe a mandibular advancement device, or mad. Comfortable to wear, it will help, with snoring and osa. Can reduce the pressure needed from cpap, or perhaps consider a nasal pillow too. He will also need a referral, to a dentist trained in sleep disorders. I would add the importance of eliminating the cause of the congestion and the use of the decongestants prior to mad use.
Sleep apnea. If CPAP did not work for your husbands osas, then he needs reevaluation, the use of more advanced forms of therapy or different masks can be considered. Certainly a repeat sleep study will likely be needed. The use of a mandibular advancement device in association with CPAP or other therapies may be appropriate. If his disease is as severe as you imply then go back to his md.
Oral Appliances. According to 2006 american academy of sleep medicine practice parameters, oral appliances are indicated for use in patients with mild or moderate obstructive sleep apnea who prefer them over CPAP and should be completed by a dentist with advanced training in sleep medicine.
ENT and dentist. I would see an ENT dr. To determine the extent of his issues- could be allergies, deviated septum, lifestyle deficiencies. Then consider reusing the cpap, but if it doesn't work again, an oral mouthpiece may be hist best option.