PostgreSQL replication not working after base backup
Your base backup looks old as current master (earlier slave) must be on timeline greater than 1 after getting promoted as master but your slave is on still timeline 1.
You can either create a new slave from scratch after taking a new base backup from new master.
Or you can try timeline switch in the current non replicating slave (not sure about it) refer it here http://paquier.xyz/postgresql-2/postgres-9-3-feature-highlight-timeline-switch-of-slave-node-without-archives/