First, welcome to the forum. I hope we can offer you the support and advice you seek.
Cyclothymia is a mood disorder. It is a mild form of bipolar disorder. Finding the right medication to stabilize the moods is difficult as no medication works for all. It is a trial and error approach to finding the medication that works for you. Your doctor will work with you to find what works well. If you are still struggling you may need to look at the medication again. The dose may need to be adjusted or another medication may be in order. Your doctor needs to know what is happening with you. Be sure you report to your doctor that you are still experiencing mood swings and it is affecting your performance at work. You may want to write down all your symptoms or fill out a mood chart. Just do a web search for "mood chart". You will find many types. Find one that works for you. Fill it out daily. It will allow you to keep track of your moods and the doctor will be able to better evaluate the efficacy of the medication.
I have 2 children with bipolar disorder. I was expecting the medication to eradicate all the symptoms and stabilize their moods completely. This has not been the case. Perhaps it is more difficult to stabilize children. They still have episodes of depression and mania but they are less severe. I have come to accept this and just keep working to try and find something that will bring about more stability.
You may want to talk to your doctor about taking fish oil. There were double blind studies done and the results overwhelmingly showed that fish oil can and will stabilize moods. It is not a quick fix; it takes about 4-6 weeks before maximum efficacy is reached. The standard dose is 2-4 soft capsules per day, yeilding 2000-4000 mg per day.
I encourage you to talk to your doctor about your continued mood swings.