What were the areas of conflict between the Bengal nawabs and the East India Company?

After the first British factory was set up in 1651 on the banks of the river Hugli, the East India company started allowing more of its merchants and traders to visit and settle down in the city of Bengal. The reasons that caused the conflicts between Bengal nawabs and East India Company were:

1. Nawabs denied concessions to the East India Company on many occasions
2. Nawabs also demanded large tributes from the company
3. The company denied paying taxes

d. The company officials wrote insulting letters to the nawabs