Gong saves call recordings and transcripts for three years.
This policy does not include calls that you place in the library, which are not automatically deleted after three years, and are available until you delete them from the library manually.
To apply the retention policy to calls in the library too, go to Company settings > Data protection and privacy and toggle on "Apply retention policy to calls stored in library". This will automatically remove calls in the library once they have reached the limit of the company retention policy too.