Update wording in section title

src/guide/communicating_fees.md

@@ -162,7 +162,7 @@ Here is how you can build this message:
 </custom-tabs>
 
 
-### Receive onchain
+### Receiving an on-chain transaction
 For receiving onchain, there is a minimum and a maximum amount the user can receive. The fees are made up of the same components as receiving a lightning payment.
 
 The user gets an onchain address from `receive_onchain`. There is no way to know ahead of time exactly the amount that will be received on this address, so it is recommended to show the user the receivable boundaries and the fees involved: