Rainbow Vacuum and Purifier Service in Istanbul Overcharges

I’ve been using a Rainbow vacuum for 25 years and a purifier for the last 4 years, but the service in Istanbul is incredibly unprofessional and unethical. There are 4-5 different service providers, and each one operates independently. Every week, I get a call claiming it's time for maintenance on either the vacuum or purifier. Each service provider quotes a different price, and they seem to follow a “charge whatever they can” approach. Every technician criticizes the previous one, saying things like, “They overcharged you” or “They installed the wrong part.”

Most recently, I paid ₺11,000 for purifier cartridges and vacuum maintenance, but just two days later, I received a call demanding more money. When I questioned the extra charges, they quickly apologized and hung up. I’m tired of the harassment and dishonesty from Rainbow's Istanbul service. The headquarters should be aware of this situation, and other customers need to be informed. Rainbow, please fix this!