You can get all the information about an active transaction with the following query
SELECT trans.session_id AS [SESSION ID], ESes.host_name AS [HOST NAME],login_name AS [Login NAME], trans.transaction_id AS [TRANSACTION ID], tas.name AS [TRANSACTION NAME],tas.transaction_begin_time AS [TRANSACTION BEGIN TIME], tds.database_id AS [DATABASE ID],DBs.name AS [DATABASE NAME] FROM sys.dm_tran_active_transactions tas JOIN sys.dm_tran_session_transactions trans ON (trans.transaction_id=tas.transaction_id) LEFT OUTER JOIN sys.dm_tran_database_transactions tds ON (tas.transaction_id = tds.transaction_id ) LEFT OUTER JOIN sys.databases AS DBs ON tds.database_id = DBs.database_id LEFT OUTER JOIN sys.dm_exec_sessions AS ESes ON trans.session_id = ESes.session_id WHERE ESes.session_id IS NOT NULL
and he will give below a similar result 
and you close this transaction using the help below KILL , specifying the session ID
KILL 77
Rinoy Ashokan Aug 08 '17 at 12:20 2017-08-08 12:20
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