GMAIL automations URL "_" problem

I have created URL for the prefilled form via formula.
As described I used prefill_ where the underscore is used. The URL works fine from the base.
The problem is when I use this URL in automation via GMAIL the “" underscore is removed.
Only the last "
” is there.
Why? Any help?

Here is the link after email received (sorry i removed part of the link): Januar=21.8&prefill Februar=-3.2&prefill ROK=2020-oproti-2019&prefill HOTEL=Hotel-SET&prefill Marec=-63.9&prefill DATA-TYP=Obsadenost&prefill April=0&prefill Maj=-59.8&prefill Jun=-69.8&prefill Jul=-42.7&prefill August=-55.8&prefill September=-46.1&prefill Oktober=&prefill November=&prefill_December=