hey guys in my extra 300 foamie when i was coming in yesterday for a landing the plane would lock up then act normal and kept doing it. i have a turnigy rx and tx the rx was in a plane that crashed

A undue drop in voltage to the RX will do that.

As will a loose TX battery connector, causing the RX to go into "hold" mode while the signal is lost.

Kinda expected from the lowest end product available, especially if it went in once already.
New electronics aint cheap, but likely cheaper than dumping in entire airframes...Upgrade or replace susepcted components.