You shouldn't have filled vessels with gas (6)

I believe the answer is:

thanks

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'you shouldn't have' is the definition.
('you shouldn't have' can mean 'thank you')

'filled vessels with gas' is the wordplay.
'filled vessels' becomes 'tanks' (tank is a kind of vessel. I am not sure about the 'filled' bit.).
'with' is an insertion indicator.
'gas' becomes 'H' (chemical symbol for hydrogen).
'tanks' placed around 'h' is 'THANKS'.

Can you help me to learn more?

(Other definitions for thanks that I've seen before include "Brief expression of appreciation" , "I am grateful" , "I appreciate that" , "Polite acknowledgment" , "Word of appreciation" .)

I've seen this clue in The Guardian.

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