It is perfectly acceptable to leave jobs off your CV (also commonly called a resume). Your CV is an overview of your most relevant experience and skills for the specific position you are applying for, not a list of every job you’ve ever held in your lifetime.
Your CV should highlight any position relevant to the job you are applying for and leave off any jobs that won’t improve your chances of getting a call back for an interview.
Any roles that aren’t relevant to the particular career path you are following should be left off your CV. For example, the babysitting or dog-walking you did when you were a teenager won’t necessarily help you get hired in a reception role, especially if your last 2 roles were in a similar reception position.
However, be prepared to discuss any gaps in your CV during an interview. Have an answer for why you didn’t mention this role if the hiring manager asks what you were up to in between positions.