Fees will increase for the first time in six years, by a weighted average of 21 percent for most applications and petitions.   This increase is necessary to recover the full cost of services provided by USCIS. These include the costs associated with fraud detection and national security, customer service and case processing, and providing services without charge to refugee and asylum applicants and to other customers eligible for fee waivers or exemptions.

https://www.uscis.gov/news/news-releases/uscis-announces-final-rule-adjusting-immigration-benefit-application-and-petition-fees