Destiny 2 developer and publisher, Bungie, has announced that the Destiny 2 service will be transferring to a new PC platform on October 1, 2019.
You will be able to migrate your Guardians, gear, game progress, product licenses and Silver currency balance from Blizzard at no cost. The last date that Destiny 2 will be accessible via is September 30, 2019. 

Blizzard and Bungie are committed to making this transition as simple and seamless as possible for the Destiny 2 PC community. We know you’ll have more questions about this, and we’ll have more answers later this summer. In the meantime, for the latest information or updates, please ensure your Blizzard contact email is up to date or visit Bungie’s website.