Entering data in in 1st blank cell in specific row

I have created a form where a date and remark is added every few days. I am using Phone Number as the base of VLookup. I want a code so that the date and remark which is entered in a Text Box, is stored in the first available blank cell pertaining to that employee. I want the first date and remark to be under "Date 1" and "Remark 1".

Thereafter, if another remark is subsequently added for that employee, the form would ask to enter his phone number to identify which employee the remark pertains to. Then the Text Box where remark is entered should be stored under "Remark 1" if there has been no remark before, "Remark 2" if "Remark 1" already exists, "Remark 3" if "Remark 2" already exists and so on.

I do not want to enter it in a new row. I want to enter the remark in the next blank cell of the row which matches the employee Phone Number.

Please Help.

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Here it is.

Any inputs would be helpful. Thanks.

Thanks for the help