Cannot use Jedis when in Pipeline. Please use Pipeline or reset jedis state - jedis

Question

I have trouble executing pipeline commands in spring data redis. I am using StringRedisTemplate. spring-data-redis 1.6.1, spring boot 1.3.2, and jedis both 2.7.3 and 2.8.0.
The code:
public void saveUserActivityEvents(Event... events) {
List<Object> results = stringRedisTemplate.executePipelined(
new RedisCallback<Object>() {
public Object doInRedis(RedisConnection connection) throws DataAccessException {
StringRedisConnection stringRedisConn = (StringRedisConnection)connection;
for(int i=0; i< events.length; i++) {
Event event = events[i];
String userId = getUserId(event.getUser());
String eventType = event.getEventType();
String itemId = event.getItem();
Integer amount = event.getAmount() == null ? 0 : Integer.parseInt(event.getAmount());
Double timestamp = Double.valueOf(event.getTimestamp());
Map<String, String> valueMap= new HashMap<String, String>();
valueMap.put("itemId", itemId);
valueMap.put("userId", userId);
String userItemEventsKey = StrSubstitutor.replace(Constants.KEY_USER_ITEM_EVENTS, valueMap);
valueMap.put("userId", userId);
String userItemsKey = StrSubstitutor.replace(Constants.KEY_USER_ITEMS, valueMap);
stringRedisConn.zAdd(userItemsKey, timestamp, itemId);
stringRedisConn.hIncrBy(userItemEventsKey, eventType, amount);
long expireInMs = TimeoutUtils.toMillis(getExpiryTimeInDays(event.getUser()), TimeUnit.DAYS);
stringRedisConn.pExpire(userItemEventsKey, expireInMs);
}
return null;
}
});
}
It blows with the exception in subject when executing pExpire.
I've tried with different flavour suggested in reference guide:
with
execute(redisCallback, true, true)
The same result. Any idea?
Thanks