Cannot add offline transactions

[ahcheing]

Firefly III Server Version: 5.7.15 Firefly III Mobile Version: 5.0.7 Android Version:
Is supported. Version >= marshmallow Device Information:
NA. Bug is present on different devices with different hardware running different versions of android. all devices run same version of app and server.

Expected Behavior

Should be able to add an offline transaction as advertised

Current Behavior

when my device is offline and I attempt to add a transaction (either withdraw or deposit or transfer) I get the following error (where ipaddress is local ipaddress):

Failed to connect to firefly.local/ipaddress

Steps to Reproduce

Note: My server is only accessible via a Lan. The server does not ever connect to the internet (it uses its own wifi card to broadcast a wifi hotspot). My android devices have no connection to the internet, can only access this home server. I have not tried to reproduce with a standard online server / standard internet connected android device, since I don't own a non-emulated android device that is allowed to connect to the broader internet.

Steps:

1. Open app when connected to lan
2. everything works as expected (including adding transactions)
3. turn off wifi on device
4. try to add another transaction. Fails.

App does not Crash

Error message disapears before I can screenshot.