I am try to add an "Amount in words" filed in my report. Since this is a cloud environment, I cannot use dlls. Infor support recommended to take a look at the public interfaces but i couldn't find any public interface for converting amount to string.

If the public interface is not there yet, you could try to get it using the procedure described in KB 2003722.

Thanks, any idea how long that takes?

Between few weeks and few months.

It seems that you got what you asked for:

KB Article 2003722 (Infor LN - Public Interfaces and Process Extensions)
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Additions for Infor LN Cloud (will be available in 2023.01)
Public Interfaces
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• Common.ConvertAmountToWords
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