Those pumps can be tricky – a couple of things for you to try first:
1: Open the pump lid again, make sure the basket is facing in the correct direction so it sits all the way in the bottom of the pump. 2. check the gasket- is it in place around the top of the pump basket area? Is there dirt or debris on it? Do you have any magic lube? It’s a water based lubricant that can help prevent air from getting into the pump. 3. Put the lid back on the pump and make sure it sits all the way down. 4. Try to tighten the handle knobs again – if they fall out of their place you may need to refit them into the bottom nut that allows it to tighten.
Next:Have you backwashed the filter? That can prevent a pump from reaching full prime – so do a backwash, then a rinse, and then restart on filter.
Also – make sure nothing is on top of the main drain in the bottom of the pool, and check the skimmer for debris – and make sure the basket is sitting all the way at the bottom of the skimmer.
If you still have issues, it’s time for a service call.