Android App Bug Fixing & Improvement

We have a Location based Android App. Previous developer have stopped communication as he could not fix the bugs due to less knowledge of Google Map grouping, Native Material Design, SQLite. We have 8-10 small coding bugs to fix , Design fine tuning as per material design animation is required. 1 new section need to be added before we go live. We need this within 1 week. It is quite urgent.