CBP officer did not update i94

I have valid i797 with i94 valid till Aug 2021. However I went to Canada this year and CBP officer updated my i94 till Dec 2020.My lawyer wants to file H1B extension to extend my i 94. Kindly note my LCA is also valid till Aug 2021.Is it possible to get it corrected by going to the CBP office or it’s advisable to apply for H1b Extension ?

Is your passport expiring by Dec 2020? Why did the CBP officer give short expiry? Any reason?

No passport validity is till 2024. Actually I just realized that i94 number did not change after my last travel . The only issue is that validity of I 94 @ CBP website is different from the i94 attached with latest i797 .But the number of i94 @ CBP website is same as the I94 attached with i797 .
my question is
Does new i94 is number given after every entry to USA?
If yes then why CBP officer did not issue new i94 number ?Is it because I crossed border by land ?
So if he did not issue new I 94 then my i94 with validity till Aug 2021 is fine or still I have to get it corrected in CBP website ??

You can call local CBP office and they can help fix the date if it was given by mistake.