please check carefully. re-open the serum GUI window to try again

hellon, my name is Djeri.. serum is my favourite VST.. and i used a lot.. Today this message appears in the serum. I do not know what to do .. and try everything .. and it does not make up .. please check carefully. re-open the serum GUI window to try again

please help me.. i don't know what to do.. i work a lot with serum..

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