Static and Dynamic networks connected to same Network Switch

Hi All,

I am having a problem configuring my office network. We have a static IP network that is used for our Main Server that allows our shops to connect remotely via VPN (Excluded Outside portion from the drawing). Due to the slow speed on the Static network of 100Mbps, my company subscribed to a Dynamic network that is 400Mbps.

I managed to hook up both networks onto a Switch which initially allowed office users to get high speeds (200-300Mbps) when connected to Router 2. However, the issue now is, at random, the network users experience a drop to speeds of 5-20Mbps which is the usual speed of the Static Network. This happens even though they are connected directly to Router 2 that is connected to the Dynamic IP Modem. One temporary fix I found was to use ipconfig /release and ipconfig /renew. However the issue comes back again and I cant expect all the network users to use command prompt.

I am not very experienced with IP Addresses. After reading up, I believe the issue is probably IP Address conflict? However after trying to configure the routers to have different IP Address ranges, I have constantly ran into issues and have been unable to solve the problem on my own.

I have drawn a picture to try to describe the setup I have done. Hoping someone with better knowledge on the subject of networks can help me out. The aim is for office users to connect to Router 2 which would provide network speeds of up to 400Mbps while still being able to print and access the file server and office printers.

https://imgur.com/a/rYlBYHx <--- Drawing of the Network Setup

Thanks in advance!

*Ps wasnt sure which flair tag to put for my post...