FreeBSD v13.1 booting device issues

I’ve installed FreeBSD 13.1 on Dell Vostro 1711 with no hard drive. So, I installed to USB stick. Every time it boots, it tells me that ufs:/dev/da1s1a has not being found and gives me the example to type in: ufs:/dev/da0s1a which I typed in manually every time it boots and it loads fine. I have been looking for the file which has that line to change it and I haven’t been able to find it. Please tell me which file is the one which has that line to change it to: ufs:/dev/da0s1a thanks in advance. Please send me email to: sergio.arana@usa.com