OpenVPN disconnects after provider IP-address changes (AUTH_FAILED)

[clickmaster_de]

My configuration is TUVPN, Fritz!box 7270v3, Pfsense 2.1-RELEASE (i386), local network with 4 win7-computers.

OpenVPN disconnects after the provider changes my IP-address. Unfortunately this happens twice a day.

Can anybody help? I read lots of recomendations but none worked for me. A friend operates the same configuration with another Fritz!box, Pfsense (amd64) and another provider and sees the same behaviour. The installation-manual I got from here: https://doc.pfsense.org/Create-OpenVPN-client-to-TUVPNcom.pdf.

I would appreciate any helpful comment.

configuration.txt
logs.txt

[clickmaster_de]

Has anybody a similar configuration that works?