I feel this might be too big of a question without additional info.
For example, is this a standard problem with which you might point to standard methods you're looking to implement? Could you point to those? (There's a good amount of research on this. )
You should offer a minimal REPRoducible EXample (reprex)? (A reprex makes it much easier for others to understand your issue and figure out how to help.) Perhaps with just a couple of meters, timestamps, and examples of missing data.
You might give more background, for example, I see a ton of obs on meter id 35 (assuming dataid is your standin for meter id), it's not clear what's missing. Are these supposed to be synchronous observations?
Having said all that, assuming your looking for synchronous observations (an obs for every meter at every minute), you might just use the last obs available.