A dismissal without prejudice means the lawsuit can be filed again without going through an appeal. However, if a motion for summary judgment was granted, the case will be dismissed with prejudice. If so, you will not be able to refile the suit.
This response is for information purpose only and does not constitute a legal advice. This response does not create an attorney-client relationship.
Assuming that this was in state or federal court, a dismissal without prejudice would allow you to refile the case within a certain amount of time. It doesn't constitute a decision on the merits which would preclude you from filing the same case in the same or another court. There can be any number of reasons a case is dismissed, including being filed in the wrong court, being filed too late or too soon, etcetera.
However, summary judgment generally means that on the facts presented (and taken as true for the purposes of the motion, unless those facts are contested by the nonmoving party by affidavit or other admissible evidence), the law dictates, in the opinion of the judge, that effectively, the moving party is "right", and I assuming here they are saying you don't have grounds to sue.
Consequently, you either accept the court's decision, or file for an appeal before the appeal deadlines, which are fairly short. You can also file a motion for reconsideration, but that is an uphill battle (getting the judge to immediately reverse himself or herself) and you're still locked into short timelines for appeal.
Finally, this is not legal advice, which is only provided after execution of an engagement agreement and review of pertinent documents and other information. This kind of public forum is not appropriate to disclose all information necessary to give legal advice, which is only given after review of pertinent documents and information and execution of an engagement agreement.