Cache expires on Redis before the TTL

Question

I am using Redis in my application. I am caching the access token on redis with the expiration time as 2 weeks(1209600 seconds). But the token get delete in within 5-6 minutes. I have monitored the same on redis terminal with TTL command. After expiring 600-700 seconds, the TTL command gives -2. I don't know how redis automatically deleting the data or expiring the cache before the expiration of TTL. Can someone please help me here that is there any configuration which I need to change on redis server. Thanks