Router not workinging with one of my client's VPN's

[Hart1951]

Have been using this router for about 18 months.  About 2 weeks ago, I was unable to access one of my client's VPN's.  After much troubleshooting, we determined the router was the problem.

Any suggestions on how to re-connect with the remote VPN after working fine for several months?  It works fine in all other aspects, but this one VPN is giving me problems.

[plemans]

How did you determine the router was the problem? 

Did anything change in the last 2 weeks? 

Have you tried using a different dns provider like googles at 8.8.8.8 or 8.8.4.4  or even cloudfare at 1.1.1.1

Also check your ipV4/6 settings.