Is it permissible to seek forgiveness by specifying a number?

It is recommended for a Muslim to increase seeking Allah's forgiveness (Istighfar). The Prophet, peace and blessings be upon him, used to seek forgiveness a hundred times or more than seventy times a day and night, as mentioned in the hadiths. If you adhere to this number, emulating him, peace and blessings be upon him, you will be rewarded. If you wish to exceed it, there is no harm, as long as you do not adopt a specific number or method not mentioned in Islamic law.