Here is a workaround though I'm not too sure of what other complications it can create. In Schedule OS, Section 2, create a dummy entry for sub-part (f) (Amount included in 1 & 2 above which is chargeable at special rates in India as per DTAA). All amount values in this entry must be zero. The catch is that there are some mandatory fields like Country, Article, etc. which would need some valid values, even though the amount is zero. Once this element is added to Schedule OS, the error goes away (I can kind of pinpoint the coding error why this is happening, based on this - something very basic!). The worry I have is that the return will have this entry under Section 2 of Schedule OS, even though the amount is zero, there will be a reference to a country and an Article and not sure if that will create issues later.
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