The most likely culprit is the time interval filter. When you first create a new view, the time interval value is “Past week,” so only requests that were created within the last seven days will match your view. Try modifying this value to see if your view behaves the way you wish.
If not, change other filter values one at a time to see which is causing your view to be blank. A value of “All” or “Any” will effectively turn the filter off.
Keep in mind that there are several filters contained within the “More filters” dropdown. If a numeric icon appears next to the “More filters” label, it indicates how many of these filters have values set.