E.g., if it is your phone, your phone service provider may prevent connections initiated from outside. The problem with that is 'wherever you are' may just as well be subject to the same restrictions your ISP places on your home LAN. At first glance, this is not necessarily a significant load on the middle party if it can be arranged that your pi could then connect independently to wherever it is your are.

If you want to connect to somewhere but you cannot initiate the connection directly, that somewhere must be connected to some other somewhere that you can connect to this is (presumably) how teamviewer works. You could try, e.g., periodically emailing the IP to somewhere, but that will not get around this if it is the case. So your real problem is that your ISP will not (consistently) allow for incoming connections. There's only one way they could do this but still allow for something like teamviewer (which it's implied in your question they do) and that's because the connection to the teamviewer server is initiated from inside your LAN, as opposed to dynamic DNS, in which the DNS is updated from within the LAN, but actual connections to services there are initiated from outside. 'my ISP (India, MTNL) blocks ports at it's will'

Raspberry pi teamviewer vpn