Why wont cobra sr 900 police scanner let you program 155.1975?

The Cobra SR 900 police scanner may not allow you to program the frequency 155.1975 due to its limited frequency range or restrictions on certain bands. Additionally, if the scanner is set to only accept frequencies within authorized public service bands, it may exclude specific channels. It's also possible that the frequency is not preset in the scanner's memory banks. Checking the user manual for programming guidelines or frequency compatibility could provide further clarity.