Change this antenna for something else, it’s beyond bad.
Stand up the RPi so the ProStick is pointing upwards.
Place a paperclip in the SMA connector with a length of 70mm.
It should stick out of the connector with a length of 66 mm.
Bonus points for radials like show here:
Be careful with not to use wire that’s too big for the SMA connector.
Basically it’s similar to this antenna, which needs some coax and at least an SMA connector: QUICK SPIDER - No Soldering, No Connector
You can also remove the plastic cover from your Nooelec antenna and basically create the above described quarter wave antenna that way.
Principle remains the same, simple wire coming from the center conductor, 66 mm long and radials which can be a bit longer connected to the shielding (ground).