Reasons that allow combining prayers
26-9-2023 | IslamWeb
Question:
Asalamu alaykom. I used to combine prayers, mainly magrib and isha, when i came back home after going out , sometimes with friends, and combined them at the time of isha. Also i once combined asr at the time of duhr before leaving the house to meet my friends. This was done in winter, as in the UK, the prayer times were close together and hard to perform on time if leaving the house. I wasn’t really aware that we weren’t allowed to do this since i asked my parents and they said they didn’t emphisise that i couldn’t. Do i have to make up for these prayers, or because i was ignorant must i not have to? Are these prayers valid, and is combining such prayers for these reasons allowed? May Allah reward you
Answer:
All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad 
is His slave and Messenger.
You should know - dear sister - that the prayer must be on the list of priorities, as it is a Muslim’s capital, so he should be extremely careful not to neglect it.
The agreed-upon excuses that make it permissible for a resident to combine two prayers are rain and illness. Some scholars are of the opinion that a resident may combine prayers when something happens that makes it difficult to perform the prayer on time based on the hadith of Ibn Abbas 
both - who said: “The Messenger of Allah combined Thuhr and ‘Asr prayers, and Maghrib and ‘Ishaa’ prayers in Madeenah without being in a state of fear or rain. Ibn ‘Abbaas was asked, ‘Why did he do so?’ He replied, ‘He intended not to cause any hardship for his nation.’” [Reported by Muslim, Ahmad, Abu Dawood, and At-Tirmidhi]
The hardship that makes it permissible to combine two prayers is not what you are accustomed to doing in combining prayers, but if you are sometimes forced to combine them out of necessity, such as being preoccupied with a need, according to the opinion of some scholars, then there is no blame on you for combining them, but do not make that a habit.
If it is confirmed that your combining of the two prayers was without a valid excuse, then whatever prayers you had combined as Jam' Takheer (prayed at the time of the latter prayer), then the prayer is valid, and it is not required to be made up.
But if you had combined them as Jam' Taqdeem (i.e., prayed them at the time of the first prayer) when it is not permissible to combine prayers, then the second prayer is not valid because it occurred before its prescribed time; hence, you must make up for it. If you were ignorant of the ruling, then we quote the saying of Sheikh al-Islam Ibn Taymiyyah 
that you are not obligated to make up for it if you were ignorant of the ruling, however making up for it is better and more prudent in any case.
Allah knows best.