Redis Sentinel - Delete keys

Question

while trying to implement sentinel on redis ( 1 master, 2 slaves), I have been unable to delete keys stored on it. If I remove the integration with sentinel, deletion works fine.

Sentinel version : 6.2.0

I check for keys with exists() and then trigger delete on the keys.

1. $redis->exists() on keys does return true.
2. $redis->del($key) -> returns zero all the time. I have tried passing keys as an array and also as single key one by one. Neither of them worked.

Before passing the key to del() method, I remove the prefixes from them.

In the Predis client interface I do see delete method as @method int del(array|string $keys). Not sure what else I could be missing.