In VBA
lesson 1: never use merged cells
lesson 2: avoid 'Select' and 'Activate'
lesson 3: avoid interaction with the workbook/worksheet as much as possible

Your file doesn't meet the criteria in lesson 1.

I think I provided all the information to answer your question.
Since the information you provided changed very often I think you best do the finetuning yourself.
If you prefer this commercial assignment to be developed further by me, you can use the paypal button in my website.
If I were your (not very poor) employer I'd prefer the latter.

PS. The inaccuracy/inconsistency of the data in your CRM-system baffles me.