In past 2 years, we've created so many links using same keywords related to our business in general as anchor text, but few links pertaining to our brand/domain name. Now we believe google considers most of these links as spam and this leads to poor results in SERP (second to the fifth page in 2 years). Now we consider three ways to restore the balance between these links: 1- Creating new links with brand/domain anchor text. 2- Purchasing links with brand/domain anchor text from sites like Fiverr. 3- Disavowing current links in Google. Deleting these links is not an option as they are widespread through the web. Which one is better? If there is a better way please let me know.