2013 – Workflow gets stuck when task is assigned to a group which contain & in its name

I have developed SharePoint 2013 workflow in SPD and task is assigned to a SharePoint security group. One of the group is HR & Admin. and when ever task is assigned to this group then workflow throws following error:

HTTP BadRequest to https://someserver/sites/somesite/_api/sp.utilities.utility.ResolvePrincipalInCurrentcontext?input='HR+&+Admin.'&scopes='15'&sources='15'&inputIsEmailOnly='false'&addToUserInfoList='True'&matchUserInfoList='true' Correlation Id: dfc163c8-b515-0fe1-af40-8cc8e27deee5 Instance Id: 0f3ecec8-d5ef-4811-b96c-bf24787ff056 

The query string "input" is missing or invalid.  

It seems the & in group name is creating problem. How to fix this issue?