If you suspect your husband is having an affair and need evidence like call recordings or SMS content, it's important to understand the legalities. Obtaining such data directly from service providers typically requires a court order or involvement of law enforcement. While call recordings and messages can be used as evidence, proving marital cruelty through other means and gathering additional proof like photos or videos might also be crucial for a divorce case. Consulting a local lawyer is highly recommended for specific advice and guidance on the correct procedures.