Thank you, Ali!
I have found that you forced using the compact mode in Taxi interface, which is not the recommended behavior. The general idea of compact mode is to use it in some forms where you need to have many items according to business needs. In other forms it is recommended to make a review and keep only most used ones and others place in groups to improve the usability.
It seems like in the compact mode the report settings form calculates size of filters panel incorrectly. And I will submit this to the developer team.
So, to fix your problem right now, you need to add a new common form of the Report settings form type and set its scaling mode to Standard. Please, see screenshots below.