Steps to reproduce (sample data, not real life case):

1. Create itemMaster:
   1. key system.localtime
   2. interval 1m
   3. 
      History storage period - do not keep
   4. Trend storage period - do not keep
2. Create itemA => Dependent item from itemMaster, add preprocessing one-line Javascript "return value % 180" (this will simply generate number 0-179 each time)
3. Clone itemA, name it itemB
4. Create trigger

{YOUR_HOST:itemA.last()} < 60
or 
{YOUR_HOST:itemB.last()} > 120

1. Optional - add recovery condition:

{YOUR_HOST:itemA.last()} >= 60
and 
{YOUR_HOST:itemB.last()} <= 120

Result:
Every 3 minutes trigger creates 2 consecutive problems each 1m long.

Expected:

There should be single problem created 2m long, because only once every 2 minutes both recovery conditions are true.