How to show dissatisfaction?

[English4everyone]

When you write a formal letter to complain about something, which one do you use? For example, a letter to an organization that didn't fulfil their promises.
a) I have a feeling of distrust about ...
b) I have a bad feeling about ...
c) I have a bad sense ...

 

[Raymott]

When you write a formal letter to complain about something, which one do you use? For example, a letter to an organization that didn't fulfil their promises.
a) I have a feeling of distrust about ...
b) I have a bad feeling about ...
c) I have a bad sense ...

Personally, I wouldn't use any of those in the first instance. It's a business letter - your feelings are not the issue.
What you need to do is draw their attention to their non-fulfilment of their promise, and ask them what they are going to do about it, or tell them what your intentions are.
They will probably understand that you are angry, disappointed, etc.