Updated with FAN 6.3.1
MODIFY
adapters/Facebook/CHANGELOG.md
adapters/Facebook/CHANGELOG.md
## Facebook iOS Mediation Adapter Changelog
+#### Version 6.3.1.0
+- Verified compatibility with FAN SDK 6.3.1.
+
+Built and tested with
+- Google Mobile Ads SDK version 8.1.0.
+- FAN SDK version 6.3.1.
+
#### Version 6.3.0.0
- Verified compatibility with FAN SDK 6.3.0.
- Now requires Google Mobile Ads SDK version 8.1.0 or higher.

MODIFY
adapters/Facebook/FacebookAdapter/GADMAdapterFacebookConstants.h
adapters/Facebook/FacebookAdapter/GADMAdapterFacebookConstants.h
// limitations under the License.
/// Facebook mediation network adapter version.
-static NSString *const kGADMAdapterFacebookVersion = @"6.3.0.0";
+static NSString *const kGADMAdapterFacebookVersion = @"6.3.1.0";
static NSString *const kGADMAdapterFacebookOpenBiddingPubID = @"placement_id";

Updated with FAN 6.3.1