credential or ssl vpn configuration is wrong (-7200)

We have VPN configured that users authenticate with LDAP (the same user and password as in Active Directory) This error message pops when one trying to log in to VPN, the temporary solution is to reset the AD password and then the user can log in to VPN, I've looked through the forums, but didn't find any solution I've got the logs from user if it helps:   2/24/2021 3:56:29 PM error sslvpn date=2021-02-24 time=15:56:28 logver=1 id=96603 type=event subtype=sslvpn eventtype=error level=error uid=C68680C1B28843D5942B67A0BCC0C687 devid=FCT8002021467391 hostname=XXXXXXXXX pcdomain=N/A deviceip=10.100.102.10 devicemac=18-26-49-2e-16-9d site=N/A fctver=6.4.2.1580 fgtserial=FCT8002021467391 emsserial=N/A os="Microsoft Windows 10 Professional Edition, 64-bit (build 19041)" user=Roy msg="SSLVPN tunnel connection failed" vpnstate= vpntunnel=Office vpnuser=XXXX remotegw=XXXXXXXXXXX

Please assist