The GRUB boot loader was previously installed to a disk that is no longer present

Hi everyone, just run a routine update this morning from GUI and the horrid GRUB screen popped up. On the following screen this comes up
GRUB install devices: │
│ │
│ [ ] /dev/sda (1000204 MB; ST1000DM003-1SB102) │
│ [*] /dev/sdb (500107 MB; CT500BX500SSD1) │
│ [ ] /dev/sdb3 (499031 MB; CT500BX500SSD1) │...

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