Sadly the issue here is with Freetrade and its platform. I have previously asked for a more user friendly message to indicate that the problem is the backend and nothing whatsoever to do with your phone or connectivity.
Unfortunately, the internal issue is not resolved and the app error message has not been improved. The issue they have said is to do with currency … I am not sure why this is the case when the share is a UK denominated one. Perhaps @Rafael will have the time to explain. All I can do is apologise. Sorry.