The graphical Overview (http://hl7.org/fhir/us/breast-radiology/2020MAY/StructureDefinition-ServiceRecommendation.html)  suggests that each Composition can have at max only a single Service Recommendation. This is not an explicit constraint in the Composition profile. As well, the narrative in this profile also suggests multiple are allowed ("which may include ServiceRecommendation instances"). Unless only a single ServiceRecommendation is allowed, please update the image.