Hi There, I have a similar issue.
iPad 8th Gen not charging. Lint and dust have been removed inside the port and I have also asked a local repairer to replace the charging port for me. They've been telling me it's an IC problem but I feel like it's just a loose port and they haven't put it back in place/done anything to try and secure it in properly.
Given that they have change the charging port and we've done a lot of the diagnostics, what's the likelihood that my iPad actually has an IC problem? Considering that it actually still charges fine when charging at an angle.
Thanks in advance!