diff --git a/src/Signal/Group/sender-key-state.ts b/src/Signal/Group/sender-key-state.ts
index 3c0c7a6..141d38c 100644
--- a/src/Signal/Group/sender-key-state.ts
+++ b/src/Signal/Group/sender-key-state.ts
@@ -94,9 +94,11 @@ export class SenderKeyState {
 		const publicKey = this.senderKeyStateStructure.senderSigningKey.public
 		if (publicKey instanceof Buffer) {
 			return publicKey
+		} else if (typeof publicKey === 'string') {
+			return Buffer.from(publicKey, 'base64')
 		}
 
-		return Buffer.from(publicKey || [])
+		return Buffer.from(publicKey)
 	}
 
 	public getSigningKeyPrivate(): Buffer | undefined {
@@ -107,6 +109,8 @@ export class SenderKeyState {
 
 		if (privateKey instanceof Buffer) {
 			return privateKey
+		} else if (typeof privateKey === 'string') {
+			return Buffer.from(privateKey, 'base64')
 		}
 
 		return Buffer.from(privateKey)