Who has a single CRM Solution, Flow and screen for both in-store and ecommerce? We currently have a CRM system for in-store sale and other solution for eCommerce Cloud and wondering if we should have a single one.

It depends. Perhaps before giving a generic answer to this very interesting architecture question, which we tend to get many times from clients, several other questions would need answering from an "as-is" analysis standpoint: 

1. How do you currently manage the integration challenges between your in-store CRM and eCommerce Cloud solutions?

2. How are your existing CRM solutions contributing to a consistent customer experience across in-store and online channels?

3. What measures are in place to ensure accurate and real-time synchronization of customer data between your in-store CRM and eCommerce Cloud systems?

4. In your current setup, how do your teams handle the dual CRM systems, and have you identified areas for operational efficiency improvements with a unified solution?

5. Considering your business growth plans, do you foresee any scalability issues with maintaining separate CRM solutions for in-store and eCommerce, and how would a unified system support future needs?

Suggest you do a proper architecture assessment (business and IT) before jumping to a conclusion. Any such decisions are very context-specific and should be tailor-made to your situation. Even if somebody said YES or NO (and there will be people on both sides) that info may not be useful for your own decision making. 

We do not have a single CRM because our business model is extremely distributed and siloed. That said, we have created a golden record repository using machine learning models to disambiguate the data and have a 270-360 degree view of the customer to achieve know your customer functionality and servicing our customers. 
Happy to discuss further in detail if interested