This is a known issue, and it involves the URI in the QR of the service providing the address you're sending to. Most commonly it has the "bitcoin:" URI, while our application expects "bitcoincash:" Our engineers are working on the issue. 

Ambiguity of addresses between BTC and BCH is detected when manually typing that same address in the address box. When there is a URI defining the coin, the QR scanner assumes the declared blockchain in the URI and does not check for ambiguity. You can test with the examples below. The first two automatically select the coin. The third behaves the same as pasting the address and asks the coin type.



Concerning initiated exchanges resulting from the above: If a Bitcoin URI is scanned and ambiguity is not checked, the app assumes a BCH to BTC exchange happens (yes, you can perform exchanges from the SEND tab in Coinomi) and launches Shapeshift/Changelly to perform it. 

When this is the case, note that the icon beside the address will  have the coin logo. You can open the disambiguation popup and manually choose the receiving coin. Just tap the address and select the "two coins" icon at the top of the screen.


If you accidentally proceeded with the transaction with the wrong coin type, and the BCH was sent to an exchange, converted to BTC and deposited into the address scanned, you can retrieve the coins if you control that address. Follow case 1 of the instructions here. You should find the address that was scanned, not the address shown in your transaction history.