Hello!
This patch should successfully test on the following systems:
Ubuntu 22.04.5 LTS
Ubuntu 24.04.1 LTS

git version 2.34.1

Try this solution:
1) Create an empty directory, copy the file 'solution.patch' into it
2) Create a script in it: (test-solution.sh)

``` bash
#!/usr/bin/env sh
set -e
set -x

rm -rf ./build
rm -rf ./ton

git clone --recursive https://github.com/ton-blockchain/ton.git
cd ton
git checkout validation-contest

cd ../

cp ./solution.patch ./ton/solution.patch
cd ./ton/
git apply --stat ./solution.patch
git am --signoff < ./solution.patch

echo apply [OK]
```

chmod +x ./test-solution.sh

3) Execute the script:
./test-solution.sh

The patch should be applied successfully.

If any other problems arise, I will be glad to help.