What are those NOV/DEZ transactions ?
Are you sure to made transactions to addresses which belong to your wallet [seed] ?
I tried to export the seed and add it in electrum but it only shows the balance/transaction of the first wallet in Blockchain.com (but i got all the money on the second wallet).
By exporting the seed to electrum, you should see all the funds in all addresses. What do you mean by "first wallet" and "second wallet" ?
Any way to access the funds?
If you own the seed then you have access to all balances in different addresses. I hope you didn't somehow send the missing amount to addresses you don't own.