Company Terminatiing without Notice Period over advance expense

Company is terminating me without notice period. Issue was with Advance money given for USA trip which did not happen. I agreed to repay with Part salary and Incentives. But company asked me to get relieved immediately. I am ready to repay advance. They have already deducted 1 and half months salary which is approximately 65% of all amount. Also company did not pay me entire last months salary. Also they have not terminated officially but stopped my access to company email account which I used to work from home. Please do advice me how can we deal with this legally. Company offer letter clearly says to give notice period of 45 days by either party in case of departing ways. If they terminate me on non payment of expenses I think logically they should give me chance to serve 45 days notice period or deduct that notice period money for advance given on fool and final and rest I can pay by check. What should I do if they reject all above things and demand money from me or take any legal action.