It is forcing me to upgrade to premium, it thinks I have sold investment. I have NOT sold any investment. I just entered the small interest gain on my bank account?

I'm not sure exactly what you mean by "interest gain." "Gain" means profit from selling an investment. How was the "interest gain" reported to you by the bank? Did they send you a 1099-series form? If so, what type of 1099? Where exactly did you enter the "interest gain"?

Did you enter a Form 1099-INT with an amount in any box other than box 1? Did you enter a 1099-DIV, 1099-B, or any other type of 1099 form? If you entered anything other than a 1099-INT with interest in box 1, give specifics of what you entered.