Tevo management neglect a revenue source.

Tevo has a 1 star rating on HelloPeter. My experience has been more positive. I purchased a Bennett Read HVC125 vacuum cleaner. It works fine and deserves a 3.5 rating. The filters need replacing after a few months, and that’s expected. However, it is difficult to get replacements. On June 1st I ordered replacement filters. After several follow-up emails, it seemed that in August (!) I would be able to get replacements. By August 30th (today) I have not received an invoice or acknowledgement that I can receive the replacements. What’s bizarre is that replacement parts are lucrative for most industries. Is this something Tevo management neglects?