The Sony Pictures Store website shut down after January 31, 2019. However, any movies you purchased should have been transferred to UltraViolet and Movies Anywhere.
If you had connected a Vudu account before the shutdown you should be able to access all of your purchased digital titles. Both services are partners with Sony Pictures, and digitally-purchased or redeemed titles should be in their records.
Once you connect your Sony Pictures Store account to Vudu (using the same email), you can then link your Vudu account to Movies Anywhere.
Both Vudu and Movies Anywhere will allow you to watch your Sony Pictures movies on supporting devices such as Blu-ray players, Smart TVs, game consoles, PCs and Macs (via web browsers), tablets, and phones.
If you didn’t connect a Vudu account before the shutdown you may be out of luck. However, you might try calling Sony Pictures support number (800) 860-2878 to see if there are any other options to access your digital movies.