guardian dental insurance misled me about my insurance coverage el paso texas

I signed up for dental insurance at the beginning of 2018 (Guardian Advantage PPO Silver) and went to the dentist and got a deep cleaning of my entire mouth. When reaching out to guardian to follow up on my claim after the work was completed, I was told that a deep cleaning is different from a regular cleaning. A regular cleaning is considered as preventive work but a deep cleaning is considered major dental work and is not covered under my policy until after being enrolled for one entire year. I don't know how they get away with this, I opted for a deep cleaning as preventive measure, I do not have any cavities and i don't understand the difference between a deep cleaning and regular cleaning. This information was never displayed or given to me.

I paid $584.00 out of pocket plus $117.36 (4 months X $29.34) and I was told I will not be reimbursed because the cleanings were considered major work and the difference between major work and preventive work is not clearly sated. Please see the attached direct from the website which describes preventive services, moderate complex dental services and major services. As you see cleanings are not mentioned under major services. Cleanings are mentioned under preventive service with no waiting period. Guardian is misleading customers!   Co-Insurance The amount Guardian pays toward the cost of a covered charge Guardian Pays    

Preventive Services Most routine dental services, including: oral exams, cleanings, x-rays 80% No Waiting Period* 80% No Waiting Period* Basic Services Moderately complex dental services, including fillings, and simple extractions 50% After a 30 day waiting period* 50% After a 30 day waiting period* Major Services More complex dental services including: crowns, implants, complex extractions, oral surgery, periodontal and endodontic services 50% After a 12-month waiting period* 50% After a 12-month waiting period*   Please also see the direct link to their website which covers the plan I applied for, no mention of deep cleanings as a major service https://mydental.guardianlife.com/our-plans/guardian-advantage-ppo-silver/