RG255C backwards compatibility with Rel-16 NR5G TDD

Hello, we would like to know if the R255C is backwards compatible with pre Rel-17 NR5G networks that work on TDD? We are doing some testing as are having problems connecting to a private Rel-16 SA network. LTE has worked fine.

Dear @CarlosR_5COMM
For RG255C, it only supports 20M bandwidth with 5G.