Como dizer "Procedente / Improcedente" em inglês

How could I say "a reclamação procede/não procede" in English?

The words "procedente" and "improcedente" have a strong meaning in Portuguese. It means the request/complain is not grounded, excessive or unjustified.

I found out the following terms:

• Founded/unfounded;
• Accepted/rejected;
• Justified/unjustified;
• Reasonable/unreasonable

Which one would be formal or common for a customer service company to use in their process?

Thanks.