Q: My transmission was slipping severely the fluid level was ok I flushed it out and add Lucas stop slips and leaks now works fine?

I’m betting that whatever is wrong with your transmission is still wrong. Some of those "mechanic in a can" liquids can buy you a little time, but more often they cause more harm than good. Most of them have additives that cause the seals and clutch lining to swell up a small amount, and sometimes that’s enough to make it work. and in your case it may be that it took some time for the clutch linings to absorb the fluid. If you don’t want to invest in a new transmission, you should probably consider finding a replacement for the car and soon, while it still works. Either way you can contact Your Mechanic to have a professional check it out. You can have a technician come out to your home or office to check out your slipping transmission and make a recommendation as to a fix or if the news is bad and you need to go shopping for another car, you can have a Pre-Purchase Inspection to check out whatever replacement you may be interested in.