Getting 404 errors when trying to install clang and libclang-dev packages using ‘apt install’

I am running into 404 errors when trying to install clang and libclang-dev packages using ‘apt install’ on **PureOS**. I am seeing the following error messages when running the command sudo apt install clang Err:1 https://repo.pureos.net/pureos amber/main amd64 libclang-common-7-dev amd64 1:7.0.1-8 404 Not Found [IP: 138.201.228.45 443] Err:2 https://repo.pureos.net/pureos amber/main amd64 libclang1-7 amd64 1:7.0.1-8 404 Not Found [IP: 138.201.228.45 443] Err:3 https://repo.pureos.net/pureos amber/main amd64 clang-7 amd64 1:7.0.1-8 404 Not Found [IP: 138.201.228.45 443] Err:4 https://repo.pureos.net/pureos amber/main amd64 libomp5-7 amd64 1:7.0.1-8 404 Not Found [IP: 138.201.228.45 443] Err:5 https://repo.pureos.net/pureos amber/main amd64 libomp-7-dev amd64 1:7.0.1-8 404 Not Found [IP: 138.201.228.45 443] Err:6 https://repo.pureos.net/pureos amber/main amd64 llvm-7-runtime amd64 1:7.0.1-8 404 Not Found [IP: 138.201.228.45 443] Err:7 https://repo.pureos.net/pureos amber/main amd64 llvm-7 amd64 1:7.0.1-8 404 Not Found [IP: 138.201.228.45 443] Err:8 https://repo.pureos.net/pureos amber/main amd64 llvm-7-dev amd64 1:7.0.1-8 404 Not Found [IP: 138.201.228.45 443] E: Failed to fetch https://repo.pureos.net/pureos/pool/main/l/llvm-toolchain-7/libclang-common-7-dev_7.0.1-8_amd64.deb 404 Not Found [IP: 138.201.228.45 443] E: Failed to fetch https://repo.pureos.net/pureos/pool/main/l/llvm-toolchain-7/libclang1-7_7.0.1-8_amd64.deb 404 Not Found [IP: 138.201.228.45 443] E: Failed to fetch https://repo.pureos.net/pureos/pool/main/l/llvm-toolchain-7/clang-7_7.0.1-8_amd64.deb 404 Not Found [IP: 138.201.228.45 443] E: Failed to fetch https://repo.pureos.net/pureos/pool/main/l/llvm-toolchain-7/libomp5-7_7.0.1-8_amd64.deb 404 Not Found [IP: 138.201.228.45 443] E: Failed to fetch https://repo.pureos.net/pureos/pool/main/l/llvm-toolchain-7/libomp-7-dev_7.0.1-8_amd64.deb 404 Not Found [IP: 138.201.228.45 443] E: Failed to fetch https://repo.pureos.net/pureos/pool/main/l/llvm-toolchain-7/llvm-7-runtime_7.0.1-8_amd64.deb 404 Not Found [IP: 138.201.228.45 443] E: Failed to fetch https://repo.pureos.net/pureos/pool/main/l/llvm-toolchain-7/llvm-7_7.0.1-8_amd64.deb 404 Not Found [IP: 138.201.228.45 443] E: Failed to fetch https://repo.pureos.net/pureos/pool/main/l/llvm-toolchain-7/llvm-7-dev_7.0.1-8_amd64.deb 404 Not Found [IP: 138.201.228.45 443] E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing? similar happens with libclang-dev: Err:1 https://repo.pureos.net/pureos amber/main amd64 libclang1-7 amd64 1:7.0.1-8 404 Not Found [IP: 138.201.228.45 443] Err:2 https://repo.pureos.net/pureos amber/main amd64 libclang-common-7-dev amd64 1:7.0.1-8 404 Not Found [IP: 138.201.228.45 443] Err:3 https://repo.pureos.net/pureos amber/main amd64 libclang-7-dev amd64 1:7.0.1-8 404 Not Found [IP: 138.201.228.45 443] E: Failed to fetch https://repo.pureos.net/pureos/pool/main/l/llvm-toolchain-7/libclang1-7_7.0.1-8_amd64.deb 404 Not Found [IP: 138.201.228.45 443] E: Failed to fetch https://repo.pureos.net/pureos/pool/main/l/llvm-toolchain-7/libclang-common-7-dev_7.0.1-8_amd64.deb 404 Not Found [IP: 138.201.228.45 443] E: Failed to fetch https://repo.pureos.net/pureos/pool/main/l/llvm-toolchain-7/libclang-7-dev_7.0.1-8_amd64.deb 404 Not Found [IP: 138.201.228.45 443] E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing? Browsing the https://repo.pureos.net/pureos/pool/main/l/llvm-toolchain-7 , I can see the packages are there, but all of them have a “+deb10u2” included in the name. For example, if you look at the first 404 you'll see apt is trying to find a package with the name **libclang-common-7-dev_7.0.1-8_amd64.deb**, but the package on the repository is named **libclang-common-7-dev_7.0.1-8+deb10u2_amd64.deb**. I only face this problem with these two specific packages, I've used apt to install several other packages and everything worked fine. I already tried the solutions suggested by apt (“maybe run apt-get update or try with --fix-missing?”). In fact, when I try running apt install with --fix-missing, I get an additional error line which says: “Unable to correct missing packages.” I also tried using apt-get instead, and I also tried running a clean, update and upgrade before installing the package with both apt and apt-get, but also without success.