In Jain achar, if a specific tap or vrut is taken with the niyam of chovihar, then chovihar is the proper and safest observance.

If you did tivihar, it is not exactly the same as chovihar. So:

• For strict palan of a tapasya niyam: chovihar is better.
• If you already did tivihar once: it is generally not counted as full chovihar.
• For your next tapasya: follow the exact vidhi as told by your guru, sthanak, or shastra-based tradition.

In short: tivihar is not equal to chovihar, so if the tapasya specifically asks for chovihar, try to do chovihar.

Jain dharm me niyam ki shuddhi aur bhavna dono mahatvapurn hain. If the intention was pure, do not worry too much, but for exact observance, follow chovihar.