According to https://gitlab.torproject.org/legacy/trac/-/issues/27821 , Tor will only support CONNECT proxies, not regular HTTP proxies. Try to use a different client or try to change some setting in IE itself so it can use HTTP CONNECT proxies.
how can I avoid
You can use a VPN if you want, but then you will be identified as a VPN user. Many companies record VPN IP addresses (it's easy to identify them).
Another option is to use something a VPS and create your own VPN with it. It's much harder to see that you aren't a normal user.
Either way will cost you money. A VPN is easy to use but a VPS is ...