93925 vs 93923 Vs 93970

hi
Can any one help me when we bill CPT® 93925,93923 and 93970 to medicare, Medicare will pay only for CPT® 93923 and other two CPT® 93925&93970 denied as not deemed medical necessity.

For CPT® 93925 billed dx 785.9 and for CPT® 93923 dx 785.9 and for CPT® 93970 dx billed was 729.81 can anybody explain what would be the possible reason claims were denied by medicare
Braddy