Electric oven keeps cutting out
It's a bad electrical connection that is failing thermally.
It works when it's cold, but when you put a load on it, it heats up. That makes materials expand and that causes a loss of connection.  Because the connection is terminated improperly.  Something like

Screws not properly torqued, causing too little pressure for it to accommodate temperature changes
Screws torqued too hard, meaning normal warming is deforming (flowing) the metal
Differences in expansion rate of aluminum vs copper, because the terminals are not designed to accommodate this with aluminum.

So every connection needs to be opened up, inspected, cleaned and re-done with proper screw torques, aluminum anti-oxidant, and with legal connections.  For instance a copper-only receptacle may need copper pigtails, with an Al-Cu splice being made with MAC Block Connectors.
It may not only be disconnecting.  It may also be doing series arcing before it fails altogether.  That makes a lot of heat and can start a fire.