OpenVPN Connect - internal android VPN stall

[camro]

Hello,
openVPN connect is working fine, but ..
my internal android VPN (to pptp) is not working, if openVPN is in the menu registered.
before connecting first time it was fine, but after first connect openVPN was writing anything into to be visible also in the internal list of VPN settings, and since this time the internal VPN not working anymore.

to reproduce:
i go to settings -> conections -> more -> VPN -> click on VPN profile to connect, then it hangs, and finally the whole android is crashing.

my system: android 7 (nougat) - samsung S8

i guess maybe it is only the method how it is writing into to make it visible on the VPN settings page, which is maybe making the problem ?
hmm, tried to reinstall the whole OS, => then internal VPN is working, but after installing openVPN again, then starting first time the connection, and seems to be registering something again, and same problem.

pls support needed - very urgent for me to be possible to use the old pptp methods and openvpn.

thx cu camel