Hey LILFROST187,
If it looks like it is leaking from around the plastic ring that is the tank sealing grommet for the filler neck.
I would advise replacing the grommet.
If it looks like it is the filler neck itself that has corroded and is porous you may be able to remove it, clean and then seal the area leaking.
I have included the instructions for removing/installing the filler neck.
Once removed you will be able to tell if you need the grommet or to repair/replace the filler neck.
Any further questions please don't hesitate to ask.
Regards, Joe
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Sunday, March 24th, 2019 AT 3:27 PM