Are the brakes adjusted properly mechanically to start with, some are electric brakes auto adjust and some you have to manually adjust and have you set up the electronic brake controller?
On my Ram, there are a bunch of different power levels and light and heavy trailer setting.
Cheers, Ray

ray ,thanks for the info that's all been done, what setting did you use light trailer or heavy.thanks again Andy

I use heavy and usually around 7 but that will vary depending on one's trailer and brakes and how they are adjusted. I set mine up so they will skid on gravel but not pavement.

Ram OEM controller is very sensitive to poor connections. I have a 2016 ram & 2004 Nash tt. The ram dealer & rv shop couldn't figure out anything & blamed the other. I had just replaced all the brakes as they needed to be at a local tire shop. I went back to them for help & they recommended me to their sister shop which they said had the best trailer brake guy in the area. I phoned him for an appointment but he couldn't get me in for a month. I explained everything I had done & he told me the first thing he would do is to replace the brake wiring front to back. I went out & got some tools & wire etc. I replaced the wire from the front junction box back to the brakes. I used Grote 2 wire brake cable 10 awg to replace the original 16 awg (12 would have worked but 10 was what they had in stock). The brakes now work perfectly. The wire I removed was cracked & broken. It would test good when stationary but as soon as you drove about 1/2 hour the brakes would fail.