This is possibly caused by having two monitors and using Service Desk on that which is corrupting the window settings for that user in the Database
Run the below Script after amending it with the user id of the affected user.
Caution: Please ensure you have a fully restorable backup of your Database before running the script.
delete from tps_application_user_setting where tps_name = 'ActionPanelConfig' and tps_user_guid = (select tps_guid from tps_user where tps_name = 'sa');
In some instances this issue has been corrected by running the following:
update tps_application_user_setting set tps_value = replace(cast(tps_value as nvarchar(max)), 'INF','0.71274961597542241') where tps_value like '%INF%'