I’m not a very experienced flyer, but I’m outraged because of the treatment received from Iberia Plus, hopefully someone in this Forum will be able to give me some advice on this issue.

After booking a flight with AA operated by IB MIA-MAD, I got a certain amount of Avios and some Elite points from the flight to Spain, but never got any point or reward from the flight back MAD-MIA. As I thought it was a mistake, I claimed the missing points but the request was denied without further explanation. Since I kept writing to the IB Plus service, I was told that it was a code L flight, and those ones do not qualify for any kind of reward.
However, the information on IB Plus website is, at least, misleading when it says:
In all direct flights between European Union, Switzerland and Norway with United States, Canada, Mexico and Puerto Rico with code and operated by Iberia, British Airways or American Airlines, will also apply the 100% of miles flown in Discount Economy, 150% in Business and 200% in First.
Minimum 500 Avios
Flights in Discount Economy:
Regardless of the distance flown, the cardholder will obtain at least a minimum of 500 Avios in all flights with AA code.
Flights in Full Economy:
A minimum of 500 Avios are guaranteed when flight distance is less than 500 miles. On a flight of more than 500 miles, real distance flown will be recorded.
The response from IB Plus for the above information is that they are entitled to change, modify, consider and deny any award from any company at anytime, and it’s the cardholder responsibility to find out which rewards you are entitled to before booking any flight, by contacting their customer service. I know that’s a disclaimer most rewards programs have, it just seems wrong to use it against your very own customers.

What options do I have now? Should I keep arguing with their “robotic-customer-service”? Or probably the best idea is try not to utilize that program anymore, just use all my avios (over 100K) and switch to AAdvantage from now on.
I will sincerely appreciate any suggestion from all you veteran and knowledgeable travelers.