How to reset UEFI Bios Insyde H2O to default ?

Friends! Chuwi Herobook 14 " laptop, UEFI Bios Insyde H2O. When booting the Ubuntu 20.04 system, a video mode error message appeared. The error started appearing after trying to install one of the programs. I went to UEFI and found several video modes in the advanced video mode settings. In the first line, I switched on to off. I decided to see if the error disappears or not. Abyss. After turning on the black screen. As Google suggested, there are no batteries on the Board. Disconnecting the power supply battery for 10 hours did not reset the settings. How do I reset UEFI settings to default? Can there be a keyboard shortcut? Or a jumper on the Board? I will be grateful for the science. There is no way to contact the service, I am very far from civilization.

write to service@chuwi.com .

Wrote. I’ll inform the community about the result.
P.S. I have already written two letters. No answer yet.

Twice I wrote to technical support about the described problem. After the second letter, they sent instructions for flashing UEFI. The instructions were sent, but there are no firmware files. I asked for a link to download or send files not mail - no answer. Wrote again - again without an answer. On the manufacturer’s website there are no files to download at all: no drivers, recovery images, UEFI firmware files. NOTHING! I wrote to tech support of a regional dealer - there is no answer. Such an attitude towards customers is disappointing. And it does not contribute to the popularization of the product. Too bad …
p.s. I use one of the paid antiviruses only because of the availability of technical support 24/7. They answer any question within an hour. Here the situation is the opposite. The purchase of this laptop will be the last purchase of this brand. Sorry.
p.p.s On a well-known Russian resource, he wrote about the quality of technical support.
https://4pda.ru/forum/index.php?showtopic=21125&st=21300#entry97560437
It will be useful for consumers to learn about things that are hidden from the buyer.