Use your last aligners for a few weeks. Chances are they will move your teeth back and get you on track. Worth a try and cannot hurt.
Unfortunately, teeth do not stay in place if you stop wearing your aligners and the next aligner assumes your teeth are exactly where the previous aligner left them. Going a month without wear is almost a guarantee of failure for the new aligners to fit. All you can do is get some retainers to hold your teeth in their current position and then new Invisalign molds and reprogram your treatment! We tell all of our patients this and STRESS what will happen if they do not follow the program!