I don't know that much about hammers, but I'd guess that something that holds it in is loose. This might mean that something has shifted when the gun was firing? (All speculation)
If I helped... then you're welcome

If not, then sorry I don't know

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Also, next time I would buy a TM pistol. You have to pay a bit more, but then once you start buying all of the replacement parts to get your WE up and running with lower performance than the stock TM or even the stock WE, you will end up paying more for a worse gun.